FBI and Fairfax County police searching for human remains have found potential evidence related to gang activity. It may be connected to two recent murders or to the disappearance of two teenage boys.

Several evidence collectors wearing white suits moved through the thick woods in Holmes Run Park on Thursday, wrapping up what officials said was "potential evidence" in what may be a gang-related crime. It's the second day of a search which has neighbors here wondering what has been found.

PREVIOUS: FBI and Fairfax Co. Police guarding discovery in Holmes Run Park

A large, white FBI truck is among many other vehicles parked at the search command post. It is set up in the parking lot of the Parklawn community pool and next to a the stream Holmes Run, which runs adjacent to a popular trail.

Police won't say what they've found or who they're searching for. But Holmes Run Park is the same park used in a 2014 brutal MS-13 gang murder. Thirteen gang members went to prison for killing a gang recruit for breaking gang rules. Officials say they stabbed him repeatedly, ultimately severing his head.

Last month, two similar MS-13 gang murders occurred in Dumfries and Springfield. The search could be related to those murders, or to two missing boys.

RELATED: 10 arrested, 4 ID'd, in gang-related murder of teen, police say

Edvin Escobar Mendez, 17, of Falls Church, and Sergio Arita Triminio, 14, of Alexandria, have been missing since September 27th. Fairfax County Police say detectives have "led extensive efforts to find them."

The investigation has led police to "believe the boys are affiliated with gangs and may be at risk."

Anyone with information is asked to contact Detective Sassano at 703-227-2027 or Crimesolvers at 1-866-411-8477.