State and local authorities continue to investigate the shooting death of a 19-year-old Concord resident.

Investigators said Zackary Sullivan, died of a gunshot wound to the neck.

“The investigation into the circumstances of Mr. Sullivan’s death remains active and ongoing. Based on information currently known to investigators, all parties have been identified and it does not appear that there is any ongoing threat to the public,” New Hampshire Attorney General John Formella and Concord Police Chief Bradley Osgood said in a joint announcement.

An autopsy determined Sullivan’s death was a homicide, but investigators were slow to release more detailed information nearly 24 hours after the shooting, including whether police had charged anyone with a crime.

Police were first called to the area of a Dunkin’ Donuts on Manchester Street Tuesday night for a report of a shooting. Not long after, Formella announced his office was assisting to investigate a suspicious death.

Wednesday morning police went to the home of George Gregoire on Airport Road, which may have been struck with gunfire. However, any link between the two incidents was unclear, as Gregoire lives 1.6 miles from the crime scene. Gregoire declined to comment further.

A heavy police presence was seen around Garvin Falls Road overnight.

John Jannini, the plow driver for Capital City Sports & Fitness, said police let him through the intersection to plow the complex around 9 p.m., but he had much more trouble getting out two hours later.