A 25-year-old man the FBI believes was responsible for an explosion that ripped through a Southern California fertility clinic left behind “anti-pro-life” writings before carrying out an attack investigators are calling an act of terrorism, authorities said Sunday.

Guy Edward Bartkus of Twentynine Palms, California, was identified by the FBI as the suspect in the apparent car bomb detonation Saturday that damaged the clinic in the upscale city of Palm Springs in the desert east of Los Angeles.

Investigators said Barktus died in the blast, which a senior FBI official called possibly the “largest bombing scene that we’ve had in Southern California.” A body was found near a charred vehicle outside the clinic.

Bartkus attempted to livestream the explosion and left behind writings that communicated “nihilistic ideations” that were still being examined to determine his state of mind, said Akil Davis, the assistant director in charge of the FBI’s Los Angeles field office. The writings seemed to indicate anti-natalist views, which hold that people should not continue to procreate. U.S. Attorney Bilal “Bill” Essayli, the top federal prosecutor in the area, called the message “anti-pro-life.”

“This was a targeted attack against the IVF facility,” Davis said Sunday. “Make no mistake: we are treating this, as I said yesterday, as an intentional act of terrorism.”

The bombing injured four other people, though Davis said all embryos at the facility were saved.

“Good guys one, bad guys zero,” he said.

Authorities were executing a search warrant in Twentynine Palms, a city of 28,000 residents about 50 miles (80 km) northeast of Palm Springs, as part of the investigation.

The blast gutted the single-story American Reproductive Centers clinic, though a doctor said its staff members were safe.

“Thank God today happened to be a day that we have no patients,” Dr. Maher Abdallah, who leads the clinic, told The Associated Press in a phone interview Saturday. —- Associated Press writer Christopher Weber contributed from Los Angeles.