Enrique Marquez, 24, a friend of Syed Rizwan Farook, 28, who launched the Islamic State-inspired rampage on Dec. 2 with his wife, Tashfeen Malik, 29, also told investigators he and Farook plotted earlier mass casualty attacks, prosecutors said.

US Attorney Eileen Decker said the two men conspired to commit 'vicious' assaults on targets including a California community college and a state highway during rush hour.

Decker said there was no evidence that Marquez took part in December 2 attack or had prior knowledge of it.

Wearing handcuffs and beige T-shirt, Marquez appeared in federal court in Riverside, California for a brief hearing yesterday. He did not enter a plea.

Farook introduced Marquez to radical Islamist ideology, prosecutors said, and by 2011 Marquez was spending most of his time at Farook's home listening to lectures and watching videos with extremist content.

At that point, the pair began planning gun and bomb attacks, the affidavit said, and Marquez told investigators their targets included the library or cafeteria at Riverside Community College, where they had both been students.

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