A New York City corrections officer was killed one day before his birthday and another man was critically injured in a skydiving accident at Skydive Long Island in Calverton July 30, officials said.

Federal authorities said the accident, believed to be the result of a mini-tornado, occurred at 4:10 p.m.

Relatives identified the deceased as Gary Messina of Medford, a New York City corrections officer since 2012 and a graduate of Patchogue-Medford High School. He was the father of one son, his family said.

Gary Messina's brother Anthony told reporters outside the family's Medford home the morning after the accident that Mr. Messina was "one of the strongest people you could know." Anthony said he nicknamed his brother "Go Hard" because of his hard-working attitude.

"Everything he did, he went hard," Mr. Messina said. "He went 100 percent, 100 percent of himself in everything that he did. He's an inspiration to so many people."

In addition to his work as a corrections officer, Mr. Messina supported his young son, Anthony Messina said.

"[He was] a father like you wouldn't believe," he said. "He loves him so much. He's the world to him and he loves that boy."

Thursday, July 31, would have been Gary's 26th birthday, Anthony Messina said.

"I love you, Gary," Anthony said through sobs. "Happy birthday."

Gary's father, Carl Messina, a former Newsday pressman, told the newspaper Thursday his son had gone skydiving every year around his birthday for the past seven or eight years.

"He was a man's man," his father told Newsday, "an inspiration to all who knew him."

The instructor was identified by police as Christopher Scott, 28, of Sound Beach. He was airlifted from Calverton to Stony Brook University Medical Center.

According to his online résumé, Mr. Scott has been an instructor at SkyDive Long Island since March 2012.
The accident was "unequivocally" caused by a mini-tornado known as a "dust devil," according to the national director of the United States Parachute Association.

Richard Winstock, who interviewed all the witnesses of the accident, said the mini-tornado collapsed the jumpers' parachute, propelling them into a free-fall toward the ground. Based on his interviews, Mr. Winstock estimated the collapse happened anywhere from 75 to 150 feet above the ground.

"All accounts confirmed that this was an uncommon weather phenomenon," Mr. Winstock said in an interview Friday. "It's commonly referred to as a dust devil."