Welcome to the News Hour. Investigators are looking deeper into the motives of two suspected teen gunmen who opened fire at an Islamic Center in San Diego yesterday.

Law enforcement officials say they were radicalized online. More than 30 guns, along with a crossbow, were found at their residences, as was a manifesto with hateful and white supremacist views targeting a range of groups.

All of this comes as the community there grieves its losses.

A growing memorial in San Diego's Claremont neighborhood reflects a community in mourning

after a deadly attack on the city's largest mosque.

The attack on the Islamic Center of San Diego began yesterday just before noon local time,

when two teenagers opened fire, killing three people.

Authorities said today the two gunmen met online and that law enforcement had found a manifesto

targeting many groups, including Muslims.

We also identified writings and various ideologies outlining religious and racial beliefs

of how the world they envision should look.

These subjects did not discriminate on who they hated.

And let me be very clear to anyone that thinks that they can end the world through violence, they are sorely mistaken.

Imam Taha Hassan paid tribute to the three victims, Mansor Kizija, Nadir Awad, and Amin Abdullah,

all he said were closely tied to the mosque.

My community is mourning.

My community is keeping our three heroes in their prayers.

My community is around the three families trying to show support and sympathy.

According to police, Mosque security guard Amin Abdullah initiated a lockdown before he died in a shootout with the suspects.

His actions, without a doubt, delayed, distracted, and ultimately deterred these two individuals from gaining access to the greater areas of the

mosque where as many as 140 kids were within 15 feet of these suspects.

Law enforcement arrived within minutes, escorting students from the center's day school

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