Live from ABC News headquarters in New York City.

This is Good Morning America.

We're going to begin with new details on that deadly shooting at the Islamic Center of San Diego.

Now being investigated as a hate crime.

Trevor Alt is in San Diego with the latest.

Good morning to you, Trevor.

Good morning, Robin. There's still a very large

police presence out here all over this neighborhood this morning, including one patrol officer

who we just saw walking through the playground here at the Islamic Center. As we're learning

about a warning phone call made by one of the suspect's mothers concerned about what he might do

and how this could have been even worse,

if not for the actions of the security guard who died protecting the people inside the Islamic

Center.

This morning, authorities revealing new details from the investigation into the horrific shooting

at the Islamic Center of San Diego, which left five people dead, including the two gunmen.

Armed teenagers opening fire, killing three people, among them the mosque security guard.

SWAT teams racing to the scene just before noon Monday.

We have confirmed three victims outside the building as well as two, reportedly two shooters.

Students inside as young as kindergartners walked out holding hands through a maze of officers with guns drawn.

I went inside the closet with my whole class. We heard like 12 or like 16 gunshots.

I tell you what got me.

Watching the kids come running out.

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