Federal agents arrested Daniel Park, accusing him of supplying chemicals used in the deadly fertility clinic bombing.
Authorities say Park began buying ammonium nitrate in October 2022 and continued until days before the explosion.
He allegedly sent 180 pounds to the bomber in January and ordered 90 more just before the attack.
Park fled to Poland four days after the explosion and returned to the U.S., where agents arrested him in New York.
FBI: Park and Bomber Planned Attack for Months
Park reportedly met the bomber, Guy Edward Bartkus, in anti-natalist online forums.
The FBI claims they bonded over a shared belief that humanity should stop reproducing.
Park traveled to California and stayed with Bartkus in Twentynine Palms for two weeks.
There, the two experimented with explosives in a bedroom and detached garage, officials say.
The FBI believes they developed bomb-making techniques during that stay.
Deadly Blast Destroys Clinic, Sparks Terrorism Probe
Bartkus died in the explosion on 17 May, which devastated a Palm Springs fertility clinic.
The blast shattered nearby windows and caused widespread damage across the area.
Officials labeled the bombing an act of domestic terrorism.
The FBI says Bartkus targeted the American Reproductive Centres, which offers fertility treatments.
Agents say he tried to livestream the attack, but failed to broadcast the footage.
Suspect Promoted Extremism for Years Online
Court records show Park frequently posted in anti-natalist Reddit forums for nearly a decade.
In 2016, he wrote about recruiting new members and called death “always an option.”
In March 2025, he sought other anti-natalists to start protests in Washington.
His post received no replies, but authorities believe he remained committed to the ideology.
The FBI found documents in Park’s home outlining explosive formulas like those used in Oklahoma City.
Officials say the case underscores how extremist ideologies can inspire acts of terrorism.