An innocent 20-year-old man was fatally shot in the neck during a broad daylight shootout with New Jersey police — that left the gunman dead and three officers injured, state officials and police sources said.

The wild encounter started with 39-year-old Kaizen Crossen firing off rounds on the 300 block of Myrtle Avenue in Irvington, NJ, just after 11:30 a.m., according to state authorities.

When cops arrived they found a 20-year-old passerby shot and Crossen, armed with a rifle and wearing body armor, and they exchanged fire, according to officials and sources.

Within minutes, the Irvington man was fatally shot by police and died a few houses away, state officials said.

Three officers were also shot — one was hit in the leg and two others were grazed by gunfire, officials and sources said.

Witnesses told ABC, they heard at least 50 rounds fired off by the gunman and cops.

The Irvington police officer who was shot in the leg was taken to University Hospital in Newark, where he was expected to make a full recovery, sources said.

New Jersey’s Attorney General’s Office is investigating the shooting, per state guidelines on police shootings.