Approval from Central HQ was granted for a manned assault excursion into the tunnels beneath Site A to try and ascertain the extent of the SCP-610 infection. The destruction of Site A and Site C have established SCP-610 can be contained and destroyed, making the source of the infection top priority. The initial descent into the tunnels consists of five teams, two research and three assault, along with enough equipment to establish an underground base of operations.
Descent into the tunnels was established using pulley systems and a lift to move equipment. Assault teams were the first to descend, armed with flame units to clean SCP-610 out of the area. All teams were able to descend without incident and flame units took point providing an undisturbed journey toward the water source where the RSCP610 drone was lost.
Base camp for underground SCP-610 operations resides at the bottom of a three-way junction, four if the water flow is included. The first pathway is that which led from Site A to Cavern HQ. The second is the pathway to the ruined village residing in the mountains above where RSCP610 was destroyed by a large unknown SCP-610 entity. The third pathway heads west and seems to follow the flow of water for an unknown distance. The cavern area here is quite large and is supported by a number of rock formations that are coated with decayed SCP-610 material. The state of this material suggests great age and appears to reinforce the structural supports. Whether or not this is intentional or coincidental is unknown.
The two research teams split activities between building Cavern HQ and collecting samples of SCP-610 in various states. No contagious materials were detected within this area and the creature recorded by unmanned drones did not appear at any point to the Cavern staff. Of the four research teams, three were ordered to proceed down the unexplored pathway while an aerial drone was prepped for a second recon of the vertical shaft.
SCP-610 infection did not appear in the third pathway until approximately 3km and serious infection did not appear until 16km in. Even after the lengths travelled by the assault teams no SCP-610 infectious life-forms were encountered and the fleshy material coating the cavern walls posed no threat to the team. The most significant reports at this time were the increasing thickness of material, suggesting a source, and the complete lack of SCP-610 contamination in the water. As a test, a sample of SCP-610 was cut away from the cavern wall and placed in the flow of water. It exhibited no unusual reactions, but was quickly swept away by the current.
At 20km in, the leader of the assault teams requested a transport buggy be dispatched to them. One was available at the above ground HQ. However, it would take time to move it to Cavern HQ and then remote-drive it to the teams. Rations provided to the assault teams were sufficient, so a camp was established while the buggy was moved and readied.
During this time an aerial drone was also sent to explore the vertical shaft. The results of this exploration were placed on hold with the arrival of the buggy at Cavern HQ and ultimately concluded in document [Data Expunged].
The buggy was navigated to the assault team encampment with no events en route, however, upon arrival and preparation to continue the exploration, the assault teams came under attack by a number of large SCP-610 infected life-forms that emerged from the area ahead of them. Video recovered from the assault team cameras show them caught off guard as the SCP-610 infected made no sound and were undetectable. On one film, for one to two seconds it appears that some of the creatures are coming out of the SCP-610 materials on the wall, not emerging from them so much as being created by the material and then breaking away to act independently.
During this assault, in an attempt to protect the buggy, ██ members were lost to the water currents and contact with them was lost. Contact was regained however and is recorded in SCP-610-L6. The remainder of the assault team now consisted of three members, armed with a single flame unit. Use of this unit to repel the assault proved vital as standard firearms did minimal damage to the infected creatures. These infected creatures show minimal traits to associate them with any known form of life in the region, giving rise to the belief they may have been spawned by the SCP-610 infection itself as a form of defense.
No further casualties were suffered during the raid and the remaining members managed to eliminate all attacking infected, allowing them to continue with exploration with added orders to attempt to locate lost team members. A further 20km into the tunnel, the river separated from the tunnel pathway and the team was instructed to abandon the recovery order, given the inability to navigate the waters safely.
A total time of ██:██:██ passed before the remaining assault team reached an end in the tunnel. At the perimeter of the area now known as Site B, the team came under assault again from a smaller number of SCP-610 that were much larger in size. These infected appeared in the tunnel as if they were lying in wait for the approaching team. These creatures were dispatched using the flame unit, although all fuel for the unit was expended in this act. The assault team was now limited to standard weapons and short range personal flame units.
A time lapse of five minutes is allowed to pass before the team proceeds further into Site B, cautious of further assaults by SCP-610 infected. The tunnel widens out into what appears to have once been a village of indeterminate age. The construction of the buildings in this area are primitive compared to the settlements at Site A and Site C, and are of clearly human construction. Many buildings rest at angles or slants, suggesting they were disturbed by a cave-in. Of interest is a building that appears to be a church with a working clock tower. This building is built atop the remains of two older buildings that have fallen completely, and has a visibly stable foundation.
Surrounding all structures in this area is a depression in the ground filled with a substance resembling a liquefied form of SCP-610 fleshy materials. The pool moves as if acted upon by minute and unseen forces, rippling outward from invisible contact points and rolling in waves from unfelt winds. The team avoids this pool at all times and proceeds through the ruins slowly on stable foundations where possible, making the church their target area.
Within the church are pews, as would be expected. However, there are only four, one of them shattered, when the building could accommodate as many as twenty. The three intact pews are arranged in a two-one formation facing a pulpit. There is no trace of dust on any surface, the entire area appearing to be immaculately clean, given the location and believed age. Behind the pulpit is a hole in the floor exposing an area of the SCP-610 'pool' beneath the building.
The church and ruins appear to be uninhabited, and exploration of the church proper is uneventful until the clock tower bell tolls. This tolling triggers a shudder in the building followed by human screams from the ceiling. Lights shone upon the ceiling reveal a large mass of SCP-610 from which descend a series of six wooden circles. Strapped to each circle is a living human coated entirely from neck to toe in SCP-610, but having an exposed head which appears uninfected. These human captives scream as the bell continues to toll and the circles move to the ground. The team begins to move toward one to investigate, when an unknown creature cries from outside the building, prompting them to take cover in shadows near the pulpit. Light sources are extinguished, pitching the entire area into darkness. Night vision is left off to avoid revealing the team's location.
Sounds continue to emit from the outside of the church, drawing closer but lower than the frantic screams of the captive humans. At least one noticed the team, as the captive humans often call out to be saved. From the entrance to the church, a candle lights on the side of the doorway, then one on the other side. A figure is seen holding a small torch and moving back and forth between a series of candles to light the doorway. The flame is then applied to a rope coated in SCP-610 which quickly ignites and spreads up to a peculiar chandelier system at the church entrance. The light from this system illuminates most of the crosses but does not reach the team's hiding place. Those captives who appear in the light do not show standard signs of the beige colored SCP-610 infection but instead are wrapped in a red variant of it which shows signs of constant motion, rippling across itself in waves.
From outside the church a flood of SCP-610 infected shamble quickly into the area, ignoring the man who lit the candles and stands in the middle of the room. They proceed to the captives on the wooden circles and begin to pull at the red SCP-610 masses resulting in further screams and cries. From what can be gathered from the returned video feed, the red SCP-610 seems to be connected to the captives and is using them as a source of sustenance that it then uses to grow and feed the normal SCP-610 infected. Overly zealous infected tear at the red mass too hard which results in pulling skin and tissue from the human captive beneath. This exposed area is quickly covered over by the red mass which then grows in size. Feeding like this continues for approximately six minutes, at which time the candle bearing figure sounds a gong and all infected entities move to the pews. There are several more creatures than seats but none move past the front most pews.
The figure who sounded the gong does not move, spontaneously collapsing as if made from hollow clay. From the pulpit area, activity is noticed as a pillar of SCP-610 flesh rises through the hole and extends, directing itself toward the gathered creatures. No sound is heard, and no motion is recorded once the pillar stops moving. This silent period persists for ten minutes without even the human captives making a sound, having fallen silent at an unknown point. The pillar of SCP-610 retracts back into the hole it emerged from without any warning, prompting the departure of the infected from the building. The candles remain lit and the team emerges after all infected appear to leave the area. The descended captives remain at ground level as well, all screaming seeming to have ceased but still showing signs of life with heavy breathing and movement.
Upon departure from the church camera feeds from all three members became erratic. Camera 1 ceases transmitting completely, Camera 2 shoots straight up into the air for several meters, and Camera 3 captures the member with Camera 2 being flung by a tendril that emerges out of the ground itself, swinging them out of sight onto the other side of the ruins. Camera 1's feed is restored and displays Camera 3's owner running briefly in the direction of the lost team member only to turn and run back as SCP-610 infected pour from between buildings.
Combat ensues between the two members and the onrushing infected using assault rifles and personal flame units, successfully driving back enough of the horde to make an escape toward the buggy. Passing by a building, Camera 1's owner is ambushed by a figure resembling the figure who was in the church lighting candles, wielding a large crop scythe. Camera 3's owner continues without pause toward the buggy location, however the buggy is found half-absorbed by the SCP-610 mass covering the floor. While turning to find another way of escape, Camera 3's owner turns to find the same figure with the scythe approaching, weapon raised. Two shots are fired and camera feed ends.
Five hours later, while final decisions were underway to decide how to contain or eradicate the SCP-610 threat, time delayed video feed from the lost team members who fell into the underground river currents was established and has been filed in SCP-610-L6.