Police: 2 San Bernardino Shooting Suspects Dead, 1 Male and 1 Female

Presidential Candidates React to San Bernardino Shooting

The FBI agent in charge of the San Bernardino shooting scene has not ruled out terrorism, Catherine Herridge reported on "The Kelly File" tonight.

"I know one of the big questions that will come up repeatedly is, 'Is this terrorism?'" David Bowdich, assistant director in charge of the FBI's Los Angeles Field Office, said in a news conference. "I am still not willing to say that we know that for sure. We are definitely making some movements that it is a possibility. We are making some adjustments to our investigation."

"It is a possibility, but we don't know that yet."

Herridge reported that a U.S. government official told Fox News that the chief assailant in the attack was an American citizen, but they did not offer many further details.

She said that intelligence and Homeland Security officials were looking into the evidence that the shooting was premeditated, including the use of assault weapons and clothing, handguns and the possible use of explosive devices.

Herridge added that the growing involvement of the FBI is a hint that the investigation is leaning toward terrorism, especially when taking into account that Bowdich appeared to be increasingly open to that possibility.

Watch more above and see Rep. Peter King react below.

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