Man sent chemicals to suspect in California fertility clinic bombing: FBI

The FBI have arrested a man at New York's John F Kennedy airport on Tuesday night in connection with last month's car bombing outside a fertility clinic in Palm Springs, California.

Authorities said Daniel Park, 32, from Kent, Washington, sent 180 pounds of ammonium nitrate - an ingredient used in homemade bombs - to Guy Edward Bartkus.

Mr Park was scheduled to appear in Brooklyn Federal Court on Wednesday, after which it is expected he will be sent to Los Angeles.

Authorities say Bartkus detonated an explosion on 17 May outside the American Reproductive Centers fertility clinic. Four people were injured and Bartkus, 25, was killed in the blast.

Bartkus left behind writings that suggest he disapproved of people being brought into the world against their will and advocated for the end of childbirth and the eventual extinction of humans.

The FBI has called the blast an "intentional act of terrorism" and said the fertility clinic was deliberately targeted.

Bartkus was a resident of Twentynine Palms, a small city about 150 miles (240km) east of Los Angeles.

Authorities said Bartkus loaded his 2010 silver Ford Fusion sedan with explosives before driving an hour from Twentynine Palms to Palm Springs.

The blast was felt more than a mile away.

At a news conference on Wednesday, US Attorney Bill Essayli said Mr Park and Bartkus spent time together conducting experiments in Bartkus' garage.

Several days after the explosion, Mr Park travelled to Denmark and then onto Poland, but was detained by Polish authorities and sent back to the US, where he was arrested.

Akil Davis, assistant director in charge of the FBI's Los Angeles field office, said that Mr Park "was in possession of an explosive recipe that was similar to the Oklahoma City bombing."

Investigators say the pair discussed plans online and were part of a movement sometimes called anti-natalism, also known as efilism.

Mr Davis referred to the site of the fertility clinic as "the largest bombing scene" the FBI had seen in southern California in recent memory.

Several buildings were damaged in the blast, including the fertility clinic with images showing a portion of its wall destroyed.

According to its website, the ARC clinic is the first full-service fertility centre and IVF lab in the Coachella Valley.

It offers services including fertility evaluations, IVF, egg donation and freezing, reproductive support for same-sex couples and surrogacy.