Prosecutors say dozens of alleged gang members in Manhattan have been indicted in connection with several crimes, including a shootout that led to the death of NYPD Detective Randolph Holder.

"Four individuals shooting…mindless, in the middle of a housing development or adjacent to a housing development at 7, 8 o'clock at night," Police Commissioner Bill Bratton said Thursday to the media.

The Manhattan District Attorney's office said 37 members of two rival gangs — the East Army Crew and 600/Gutta Gang from East and West Harlem — are under arrest in connection with 14 shootings.

Officials say one of those resulted in death of 33-year-old Holder, who was shot in the line of duty last October 20.

Holder and his partner were responding to calls of shots fired in East Harlem when he came upon Tyrone Howard.

The 30-year-old allegedly shot Holder in the head, and is now facing a first-degree murder charge.

Sources tell NY1 that a doctor testified in court earlier this week and stated that Howard admitted to being on PCP, marijuana, and alcohol.

The gang members arrested are facing 66 counts, including murder, attempted murder, and conspiracy.

"These acts of violence were simply for no other reason than to retaliate against other rivals for previous shootings and murders, which led these neighborhoods into a downward spiral of violence," Manhattan D.A. Cyrus Vance, Jr. said. "And secondly, to enhance the social status of the individuals in these gangs."

One gang member is charged in the shooting death of 18-year-old Jordan Barber last June outside a basketball tournament at the famed Rucker Park.

Prosecutors said the gangs also conspired to provide each other with intelligence about NYPD activity in Harlem and warned members not to cooperate with law enforcement.

Despite these cases, police continue to say violence is down in the city.

NYPD statistics show that the number of murders has dropped by nearly nine percent in the first six months of the year compared to the first half of last year, according to police sources. Shootings are down 21 percent.

This as another a new graduating class of officers from the police academy hits the streets for the July 4th weekend.