Dozens of officers descended upon the grounds of the now-abandoned Pilgrim State Hospital on Crooked Hill Road Thursday. Some of them were armed with shovels for digging.
Watch video from NewsCopter 7 showing the investigators at the scene:
"We are scouring that area because we found two skeletal remains in that general area and we're going to do our due diligence," said Commissioner Timothy Sini with the Suffolk County Police.
All four bodies found -- the two sets of remains and two bodies of girls -- were all teenagers.
Two sets of human remains were found close to the former hospital in an industrial area on Emjay Boulevard. One was identified as 19-year-old Oscar Acosta, who was reported missing in May. His body was found Friday. The other body, which was discovered Wednesday, has not yet been identified.
Last week, two young girls were discovered beaten to death near Ray Court in Brentwood. Police have said that Nisa Mickens and Kayla Cuevas were killed by a member or members of a gang.
"We will stop at nothing to ensure the safety the people in Brentwood and in all communities of Suffolk County," said Sini.
Stay with abc7NY for the latest on this developing story.