Jihadi killers scrupulously concealed their views, plans and a cache of weapons and explosives.
Syed Farook and his wife Tashfeen Malik destroyed all of their digital footprints one day before their planned terrorist attack.
The Islamist couple met with Al-Qaeda in Saudi Arabia.
FOX News reported:
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Investigators believe that on at least one of those trips to Saudi Arabia, one or both members of the couple made contact with suspected Al Qaeda terrorists. The exact nature of that contact was not immediately clear.
California investigators have already tracked down at least four individuals from the Los Angeles area who were previously under some sort of investigation by counter-terrorism officials and have had some sort of communication with Farook.