Transcript for New Questions on Whether the San Bernardino Shooting Could Have Been Prevented
P.M. Central, right here on ABC. And new questions about the terrorist attack in San Bernardino and whether it might have been stopped. Also tonight, inside the chase and the shootout with the police officer right behind the killers' black SUV. We'll hear from him. Here's kayna Whitworth. Reporter: Tonight, investigators testing what they dredged out of this lake after three days of searching. Still no word whether they've found any traces of that missing hard drive belonging to Syed farook and tashfeen malik. A digital footprint that could prove critical for investigators amid new questions about the screening that allowed malik into the country in the first place. Had they checked out tashfeen malik a little more, maybe she wouldn't have gotten a Visa. Maybe those people in San Bernardino would be alive. Reporter: Malik vetted by homeland security, the state department, and had a criminal background check. But investigators don't always scrub social media. After the attack they found malik's Facebook post critical of moderate muslims. Now the "New York times" reports she also talked openly on social media in support of violent jihad and "Wanted to be a part of it." I'm asking to immediately initiate a program that would check the social media sites of those admitted on Visas to see if they are using words like jihad, explosives, mass shootings. It's outrageous that this isn't already done. Reporter: Tonight, one of the officers who chased the killer couple down is speaking out. Sergeant Andy Capp. They haven't stopped. And the back window of their SUV shatters. And I see gunfire coming out of it. Reporter: The black SUV pulls over. Farook gets out and starts firing. Capps gets out to return fire. I saw him shooting at a deputy. That I know was across the street. That's when I opened fire on him. Reporter: The terrorists were killed in that shootout. The first time in his 23 years on the force that he ever fired his weapon while on duty. Kayna, thank you. Next, to the extreme weather
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