Two helicopters crashed midair in New Jersey on Sunday, killing one person and critically injuring another, authorities say.

Hammonton Police Chief Kevin Friel said rescuers responded to a report of an aviation crash at about 11:25 a.m. Video from the scene shows a helicopter spinning rapidly to the ground. Police and fire crews subsequently extinguished flames that engulfed one of the helicopters.

The Federal Aviation Administration described the crash as a midair collision between an Enstrom F-28A helicopter and Enstrom 280C helicopter over Hammonton Municipal Airport. Only the pilots were on board each aircraft. One was killed, and the other was transported to a hospital with life-threatening injuries.

Sal Silipino, owner of a cafe near the crash site, said the pilots were regulars at the restaurant and would often have breakfast together. He said he and other customers watched the helicopters take off before one began spiraling downward, followed by the other.

“It was shocking,” he said. “I’m still shaking after that happened.”

Hammonton resident Dan Dameshek told NBC10 that he was leaving a gym when he heard a loud snap and saw two helicopters spinning out of control.

“Immediately, the first helicopter went from right side up to upside down and started rapidly spinning, falling out of the air,” Dameshek told the TV station. “And then it looked like the second helicopter was OK for a second, and then it sounded like another snap or something ... and then that helicopter started rapidly spinning out of the air.”

Hammonton is a town of about 15,000 people located in Atlantic County in the southern part of New Jersey, about 35 miles (56 kilometres) southeast of Philadelphia. The town has a history of agriculture and is located near the Pine Barrens, a forested wilderness area that covers more than 1 million acres (405,000 hectares).

The FAA and National Transportation Safety Board will be investigating the crash, Friel said.

Investigators will likely first look to review any communications between the two pilots and whether they were able to see each other, said Alan Diehl, a former crash investigator for the FAA and NTSB.

“Virtually all midair collisions are a failure to what they call `see and avoid,” Diehl said. “Clearly they’ll be looking at the out-of-cockpit views of the two aircraft and seeing if one pilot was approaching from the blind side.”

Although it was mostly cloudy at the time of the crash, winds were light and visibility was good, according to the weather forecasting company AccuWeather.