Read a local report on Danroy Henry's shooting death from CNN affiliate WCVB-TV.

(CNN) -- The police chief of a New York City suburb defended his officers Tuesday, days after they shot and killed a Pace University student.

Chief Louis Alagno of the Mount Pleasant, New York, police said that officers handcuffed Danroy "DJ" Henry -- a 20-year-old resident of Easton, Massachusetts, and college football player -- after they shot him. But Alagno said that authorities removed Henry's handcuffs and tried to save his life as soon as they discovered his condition.

"This is a nightmare for everyone involved," Alagno told CNN.

A day earlier, Donna Parks -- whose son was a friend of Henry's and was shot and wounded in the incident -- told CNN that police "pulled DJ out of the car, handcuffed him, put him face down on the ground and left him there for 15 to 20 minutes."

The incident occurred after a police officer came across "a large group of unruly patrons" in front of Finnegan's Grill in Thornwood, New York, and called for support shortly after 1 a.m. Sunday, according to a police press release. Some 50 police officers responded to the brawl, which continued after the shooting incident, the statement said.

Officers were breaking up fights, police said, when "a vehicle parked in the fire lane" accelerated. A police officer tried to stop the vehicle, which Henry was driving, but its mirror struck the officer and the officer "ended up on the hood," said police.

Another officer tried to pull the first one down from the hood when the car struck him as well. The officer on the hood shot at the driver, but the vehicle continued in the fire lane in the direction of a third Mount Pleasant officer. That officer also fired at the vehicle, according to the police press release.

But Parks disputed the police account. She said Henry and others in the car were waiting for a friend to come out of the establishment "when a police officer banged ... on the window." She said Henry began driving after her son, Brandon Cox, told him that he thought police wanted him to move his car.

"Another police officer with his gun drawn just ran out in front of DJ's car," said Parks, insisting Henry had no time to stop.

Alagno, the Mount Pleasant police chief, said all the people in the car -- including Henry -- were handcuffed because it was considered a "felony stop" since gunfire was involved. He did not specify whether the shots had come from civilians, police or both.

The officers involved in the shooting have yet to return to duty, said Alagno.

Authorities have launched an investigation involving Mount Pleasant police, New York State Police and others to determine what happened. The probe, expected to take two to three months, will be "long and difficult," said Alagno, who has been Mount Pleasant's police chief since 2001.

Alagno said that he met with Henry's parents after the fatal shooting, calling the meeting one of "the most difficult things [I have] ever had to do." Henry's father was "very articulate -- much more composed than I would have been," said Alagno.

"We are besides ourselves," Henry's father, Danroy Henry Sr., told CNN affiliate WCVB. "His coach called him today a man of high moral character."

Student organizations at Pace University in Pleasantville, New York, carried lights from the school's fitness center to its football field Sunday night in memory of Henry. Parks said that the young men in the car shot at by police have never been suspended or arrested.

"They've done everything that we, as parents, have asked them to do," she said.

CNN's Ben Brumfield, Antoinette Campbell and Jason Kessler contributed to this report.