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(CNN) —  

Investigators believe San Bernardino shooter Syed Rizwan Farook may have been plotting an earlier attack in California with someone else, two U.S. officials said.

One of the officials said the two conspired in 2012 and a specific target was considered. Neither of the officials could say how serious the plotting got.

San Bernardino shooters: What we do and don’t know about their radicalization

One official said the two decided not to go through with the earlier attack after a round of terror-related arrests in the area.

“They got spooked,” the official said.

The purported plot bolsters assertions law enforcement officials have made since the San Bernardino attacks, saying Farook had been radicalized for a time before the shooting.

Who was Tashfeen Malik?