What is pro-mortalism, the belief held by Guy Bartkus?

The man suspected of bombing outside a California fertility clinic expressed “nihilistic ideations,” authorities said on Sunday – and had written a “pro-mortalist” manifesto, according to unverified reports.

Guy Edward Bartkus, 25, was attempting to livestream the bombing attack on American Reproductive Centers fertility clinic in Palm Springs, authorities said during a Sunday press conference.

Bartkus also expressed “nihilistic ideations,” and left writings still being reviewed by investigators, Akil Davis, the head of the Los Angeles FBI office, said.

Sources told The Associated Press and KCAL News that in those writings, Bartkus expressed a belief that the world should not be populated.

According to reports and a website purportedly belonging to Bartkus, in some of the alleged writings, Bartkus described himself as a “pro-mortalist” and said he believed people did not give consent to exist.

He described being “pro-mortalist” as being who intends to bring about their own death as soon as possible in order “to prevent your future suffering, and, more importantly, the suffering your existence will cause to all the other sentient beings.”

He also allegedly wrote that his end goal was to begin “sterilizing this planet of the disease of life” on the site.

Bartkus also allegedly left a 30-minute audio recording explaining his motive behind the attack.

“I figured I would just make a recording explaining why I’ve decided to bomb an IVF building or clinic. Basically, it just comes down to I’m angry that I exist and that, you know, nobody got my consent to bring me here,” he allegedly said in the recording.

Bartkus allegedly went on to say that he was “angry” that IVF clinics exist.

“These are people who are having kids after they’ve sat there and thought about it. How much more stupid can it get?” he says in the purported clip.

The Independent could not immediately verify these reports, and authorities did not share details of Bartkus’ writings on Sunday.

The bombing on Saturday morning, which authorities called an “intentional act of terrorism,” left four people injured in addition to killing Bartkus.

The explosion damaged the clinic’s office space, where it conducts consultations with patients, but left the IVF lab and all of the stored embryos there unharmed.

The incident is being investigated as an act of terrorism, officials said.

Authorities said Bartkus is a resident of Twentynine Palms, home to a large marine base about an hour from Palm Springs. The FBI and San Bernardino County Sheriff’s deputies have also searched Bartkus’ home.

The FBI has not shared how it determined the explosion was an act of terrorism, or provided details about the writings left behind, or a possible motive in the attack.

The Associated Press contributed to this report.