Four New Yorkers were charged on Wednesday in connection with strange circumstances involving human remains found scattered across Long Island , the Suffolk County Police Department announced .

Steven Brown, 44, Jeffrey Mackey, 38, Alexis Nieves, 33, and Amanda Wallace, 40, were charged with hindering prosecution, tampering with physical evidence and concealment of a human corpse after more remains were located on Tuesday, according to a press release shared by the police department on Wednesday. None of the four have been charged with murder.

The investigation began on Feb. 29, when a student walking to school discovered a severed left arm in Southards Pond Park in Babylon. The students father called 911 to report the limb to police.