A man who was expecting his first child was killed Sunday and his brother was injured when a device they were preparing for a gender-reveal party exploded in a garage in the Catskills in New York, the authorities said.

The New York State Police said troopers responded to a report of an explosion at a home in the town of Liberty, just before noon. Christopher Pekny, 28, died and his brother Michael Pekny, 27, was hurt, officials said.

What set off the explosion remained under investigation, a spokesperson for the State Police, Trooper Steven Nevel, said. The device consisted of some kind of pipe that was intended to be used at a gender-reveal party, but the nature of its explosive material was not yet known, he said.

Peter Pekny Jr., 34, the oldest of the brothers, called what happened “the freakiest of freak accidents that I could ever imagine,” though he did not know what had set off the explosion, he said in a telephone interview today.

He said that his brother Michael was in stable condition at a hospital in Middletown, New York, and that doctors were able to rebuild a damaged knee.

Explosive devices used at gender-reveal events have been linked to at least two deaths since 2019 and two major wildfires. The parties are a popular way for couples to announce news about their pregnancies on Facebook and Instagram.

A 26-year-old man died in Michigan this month after he was hit with shrapnel from “a small cannon type device” that exploded when it was fired in celebration at a baby shower, the authorities said.

Peter Pekny said that his brothers were “very mechanically inclined” and that “they could fix and do anything.”

He described Christopher as a gifted mechanic who liked to rebuild motors and to take cars apart and put them back together. Christopher and Michael had been fixing up a rental house in Ferndale, a hamlet in the town of Liberty, which is about 110 miles northwest of New York City, their brother said.

Pekny said Christopher earned the nickname Frankenstein at his job at Liberty Concrete, where he worked as a mason.

“What he picked up and moved around would have taken three people,” he said. “I’ve seen him pick up engine blocks because they were in the way.”

He said Christopher Pekny was 6 feet 5 inches tall and weighed 250 pounds. When he played high school football, he once ran so forcefully into another player that he cracked the player’s helmet in half, he recalled.

“He had the hardest head I’ve ever seen,” he said.

Christopher Pekny learned just before Christmas that his girlfriend was pregnant and that they were having a boy, Peter Pekny said.

Pekny said he got a call from family members Sunday — the day of the party — while he was in Florida, New York, about 45 miles away. He thought at first that the call was a ruse to get him to the party early, but when he learned the news, he raced to Liberty on Route 17, at times faster than 100 mph.

He said he blew by a state trooper, who pulled him over and started yelling at him. Pekny said he explained why he was speeding, and after the trooper went to his patrol car and checked on the radio to verify his story, he returned to Pekny’s pickup truck.

He said the trooper told him, “You gotta go” and did not ticket him. “The color completely ran out of his face,” Pekny said of the trooper. “He looked like he saw two ghosts.”

As boys, Michael and Christopher were inseparable and remained that way into adulthood. “If you could think of any two people who were the closest two people — amplify that tenfold,” Pekny said.

As he was growing up, Pekny said, he was rough on his younger brothers and did not share their bond. That had started to change recently, he said, and they were growing closer.

“He was really looking forward to starting a family,” he said of Christopher. “He was really starting to settle down and grow up.”

The Pekny family owns the Robin Hood Diner, a mainstay in Livingston Manor, an area of the Catskills renowned for its trout fishing.

Christopher, who would have turned 29 on Tuesday, waited tables and tended bar there. He wished his father good night Saturday, saying he would see him in the morning, Pekny said.

A Facebook post on the diner’s page said: “We appreciate the overwhelming display of love and support that you all have shown. The Robin Hood will be closed for the immediate future.”

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