The FBI says both San Bernardino shooters honed their skills with target practice at gun ranges around the Los Angeles area before last week's attack. The FBI also believes that Syed Farook and Tashfeen Malik had been radicalized for "quite some time," David Bowdich, of the FBI's Los Angeles office, said Monday.

"We do have evidence that both of the subjects participated in target practice in some ranges within the metro area or within the Los Angeles area," Bowdich said. "That target practice in one occasion was done within days of this event."

Bowdich also said that the FBI now believes that "both subjects were radicalized, and had been for quite some time."

He did not say how long the attackers had been radicalized or by whom, stressing that there is still no evidence that the shooters were connected to a terror group.

Bowdich also said that investigators had found enough material for 19 pipe bombs, not the 12 initially initially disclosed.

"Ultimately, it appears there are 19 pipes in that house that we have removed," he said.

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