Palm Springs Fertility Clinic Bombing Suspect Found Dead in L.A. Prison

A man accused of being involved in the bombing a fertility clinic in Palm Springs last month was found dead in the Los Angeles federal prison on Tuesday.

Law enforcement sources tell TMZ ... Daniel Park, who was charged with providing a shocking amount of chemicals used to make the bomb, was "found unresponsive" in Metropolitan Detention Center ... and declared dead after staff's life-saving measures were unsuccessful.

For the moment ... just what exactly happened to Daniel is not clear.

Park was accused of providing 270 pounds of ammonium nitrate to the primary suspect -- Guy Edward Bartkus, who authorities say carried out the May 17 car bomb attack. Four people were injured in the attack ... but Bartkus, of Twentynine Palms, California, was the only person killed in the blast.

Bartkus reportedly held "anti-natalist" views, meaning he thought humans need to stop procreating. He is reported to have left behind "anti-pro-life" writings before he allegedly set off the bomb.

Akil Davis, the assistant director of the FBI’s Los Angeles field office ... at the time called the attack an "intentional act of terrorism."

While the physical clinic was damaged, no embryos were harmed.