Police say they are investigating the death of a teenager whose remains were discovered in Brentwood.

According to police, the body of Jose Pena-Hernandez, 18, of Brentwood, was discovered on Oct. 17, in a wooded area at Pilgrim Psychiatric Center.

Pena-Hernandez, a known MS-13 gang member, was reported missing on June 13.

An autopsy will be conducted by the Office of the Suffolk County Medical Examiner to determine the cause of death.

The death is the sixth homicide in Brentwood since September. Suffolk Police Commissioner Tim Sini says all the cases show gang involvement, but he did not confirm if they were related.

"We didn't find those remains by accident," says Sini. "These officers put pressure on these gang members. They collect intelligence. They make arrests."

Since September, Sini says more than two dozen MS-13 gang members have been arrested and five are facing federal charges.

The commissioner says there will be increased patrols.

Sini says this is the third set of skeletal remains found in the area of the Pilgrim Psychiatric Center. He says police have no plans to search that area, but plans can change.