A Washington state man charged with supplying explosive chemicals to the bomber of a Southern California fertility clinic in May was found unresponsive in federal custody on June 24 and taken to a hospital, where he was pronounced dead, according to the Department of Justice (DOJ).

Daniel Park, 32, was arrested at New York City’s John F. Kennedy Airport on June 13 after being extradited from Poland. He allegedly fled the United States four days after the May 17 bombing in Palm Springs, Calif., according to officials.

Park was charged with malicious destruction of property and was awaiting trial at the Metropolitan Detention Center in Los Angeles.

Employees at the center started lifesaving measures on Park when they found him unresponsive at about 7:30 a.m. Tuesday. Emergency medical services were requested, the DOJ reported.

“Mr. Park was transported ... to a local hospital and subsequently pronounced deceased by hospital personnel,” the DOJ announced in a press release.

Officials did not release details about what led to Park’s condition Tuesday morning.

Investigators say Park worked with the suspected bomber—Guy Edward Bartkus, 25, of Twentynine Palms, who died in the explosion—by providing chemicals and helping to test bomb-making materials in California months before the attack.

According to officials, Park and Bartkus met in online forums for anti-natalists, people who oppose human procreation. Their ideology apparently led them to target the American Reproductive Centers fertility clinic, which helps women become pregnant.

Officials allege the bombing was an act of domestic terrorism and may be the largest such attack ever in Southern California.

FBI officials said they were “fairly confident” that the alleged bomber was Bartkus, who was found dead near a vehicle that contained the bomb.

“The subject has nihilistic ideations, and this was a targeted attack,” said Akil Davis, assistant director of the FBI’s Los Angeles field office, during a May 18 press conference. “We believe he was attempting to livestream it, and yes, that is also part of our investigation.”

Davis reported the vehicle used in the bombing was a silver 2010 Ford Fusion, a sedan.

The investigation revealed that Park had purchased and shipped a total of 270 pounds of ammonium nitrate to Bartkus between October 2022 and May 2025. Just days before the explosion, Park bought an additional 90 pounds of the chemical, according to a federal complaint cited by the DOJ.

The bombing injured four other people, but all embryos at the facility were saved, according to officials.