The attackers behind the deadly shooting in San Bernardino, California, last week had both been radicalized "for some time," the FBI said Monday.
David Bowdich, the assistant director in charge of the FBI’s Los Angeles office, confirmed speculation to the effect of the killers' radicalization, but said that investigators have not yet determined whether the attackers, Syed Rizwan Farook and Tashfeen Malik, were self-radicalized or subject to influence from others, Politico reported.
Bowdich also said that it remains unclear whether Farook, a U.S. citizen who had traveled to the Middle East multiple times, was influenced by Malik, his wife who was a Pakistani national. Bowdich also noted that radicalization often happens "on the Internet."
"We do not see any evidence so far of ... an outside the continental U.S. plot. We may find it someday, we may not. We don’t know," Bowdich explained.
Evidence suggests that the attack was planned ahead of time, Bowdich stated, pointing to the fact that the attackers went to target practice at a gun range in Los Angeles "within days" of Wednesday’s shooting at a San Bernardino holiday party, which killed 14 people and wounded 21 others.
The FBI official labeled the investigation "massive in scale," adding that investigators have already conducted approximately 400 interviews and gathered 320 pieces of evidence. Investigators also intend to hold meetings with family members of the victims.
"That is a crucial part for us to allow them to ask questions and so that we can address them face-to-face and talk to them about our full commitment," Bowdich explained.
The FBI has been investigating the gun attack as an act of terrorism since Friday after evidence was discovered indicating that Farook had contact with Islamic extremists in past years. Officials also found that Malik pledged allegiance to the leader of the Islamic State, Abu Bakr al-Baghdadi, on social media while the attack was occurring late Wednesday morning.
After opening fire on the party for San Bernardino County’s health department, both attackers fled the scene. They died in a shootout with police later in the day.
In addition to thousands of rounds of ammunition, law enforcement officials found 19 pipes in the Redlands home of the attackers that could have been made into pipe bombs, Bowdich clarified Monday.
"Ultimately it appears there are 19 pipes in that house that we removed ... that is not 19 pipe bombs, let me be clear. That is 19 pipes that could be turned into pipe bombs if all the components are there and present for them to actually be construed that way," Bowdich said.