Nassau County police are investigating a possible murder-suicide in Mill Neck on Monday morning.

A police spokeswoman said officers responded to an altercation between a man and a woman in a minivan on Oyster Bay Road at 8 a.m.

Upon arrival, they found both dead of what appeared to be gunshot wounds. A handgun was reportedly found in the vehicle.

Homicide Squad detectives are continuing the investigation.

County medical examiners are conducting autopsies on the pair to determine their cause of death and identities.