By Steve Gorman
LOS ANGELES (Reuters) - The California man accused of buying assault rifles used by the married couple who massacred 14 people at a San Bernardino office party in December 2015 pleaded guilty on Thursday of conspiring with one of the killers in previous plots.
Enrique Marquez Jr., 25, was convicted on charges he conspired with Syed Rizwan Farook in 2001 and 2012 to provide material support to terrorists for planned attacks on a community college and a freeway that were never carried out.
Marquez is slated to return to federal court in Riverside, east of Los Angeles, on Aug. 21 for a sentencing hearing, where he faces a maximum penalty of 25 years in prison, according to a spokesman for the U.S. Attorney's Office.
The defendant, a friend and former neighbor of Farook, also pleaded guilty to lying on a federal firearms form when he bought assault rifles for Farook, one each in 2001 and 2012, prosecutors said.
Those guns, which Marquez falsely claimed he purchased for himself, were used by Farook, 28, and his wife, Tashfeen Malik, 29, when they opened fire at a holiday gathering of Farook's co-workers on Dec. 2, 2015, killing 14 people and wounding 22 others.
Farook, a U.S.-born son of Pakistani immigrants, and Malik, a Pakistani native he married in Saudi Arabia in 2014, died in a shootout with police four hours after the massacre.
Authorities have said the couple were inspired by Islamist militants. At the time, the assault ranked as the deadliest attack by Islamist extremists on U.S. soil since the Sept. 11, 2001, attacks by airline hijackers. In June of last year, an American-born gunman pledging allegiance the leader of Islamic State, shot 49 people to death at a nightclub in Orlando, Florida, before he was killed by police.
Marquez did not take part in the San Bernardino rampage. But according to the Federal Bureau of Investigation, he called 911-emergency operators after the massacre to say he wanted to kill himself, admitting he had bought a weapon used by Farook. Marquez then checked himself into a mental health facility.
FBI agents later raided his home and questioned him for several days before he was arrested. He has been custody ever since.
Marquez still faces immigration fraud charges stemming from his sham marriage to Russian-born Mariya Chernykh, 26, prosecutors said. She and Farook's brother, Syed Raheel Farook, 31, pleaded guilty in January to immigration fraud.
(Reporting by Steve Gorman; Editing by Andrew Hay)