The death of the man who authorities say was fatally knocked off of his motorcycle by an object thrown by an NYPD sergeant has been ruled a homicide, the medical examiner said Friday.

According to the medical examiner, Eric Duprey’s cause of death was blunt force trauma to the head.

According to the New York State Attorney General’s Office of Special Investigation, which is leading the investigation into the incident, NYPD Sergeant Erik Duran threw a picnic cooler at Duprey, which caused him to fall off his motorcycle, in an attempt to stop him from fleeing at around 5:30 p.m. Wednesday.

According to police, a group of plainclothes narcotics officers were carrying out "buy-and-bust" anti-drug sale operations in the Bronx's 52nd Precinct at that time when they tried to arrest a 30-year-old man for selling narcotics.

The NYPD says Duprey fled on a motorcycle, and police pursued him to 2523 Aqueduct Ave. in Fordham Manor. According to the Office of Special Investigation, Duran threw the picnic cooler at Duprey in the vicinity of that location.

Duprey then lost control of his motorcycle, struck a parked vehicle and fell to the ground, police say. Emergency responders pronounced him dead at the scene at around 5:35 p.m., the NYPD says.

Duran was suspended from duty Thursday morning, an NYPD spokesperson said in a statement.

Jonathan Roberts, an attorney for the Duprey family, told NY1 in a statement Saturday that "the individual who committed this heinous act must be held accountable."

"Another young man gone too soon at the hands of a reckless police officer — a loving partner, father, and son who provided financial and emotional support to his family," Roberts said.