As the FBI continues its investigation into last week's rampage, a number of law enforcement agencies are urging mosques to help them prevent such heinous crimes from happening again.
But the relationship between Islamic communities and the authorities is a very complicated one, especially in Southern California.
In the mid-2000s, a covert program called Operation Flex monitored mosques in Orange County.
It found few terrorist connections but a lot of controversy from the local community.
FBI informant Craig Monteilh infiltrated the Islamic Center of Irvine, and he was told to act like a radical.
But in 2007, the Center put a restraining order on him for erratic and agitating behavior. They also reported him to the FBI, not knowing he was an FBI informant.
Monteilh later spoke out against the program and called it entrapment, blowing the FBI's cover and angering the local Muslim community.
To look at how the government can build a better relationship with the local Muslim community to root out radicals, we're joined by Mustafa Umar, founder and director of the College of Islamic Studies located in Orange County.