Kenney On Vegas Shooting: 'I'm At A Loss For Words To Say How We Can Prevent This'

PHILADELPHIA (CBS) -- Philadelphia Mayor Jim Kenney questions the gun laws that allow someone to acquire automatic weapons capable of shooting hundreds of people at once.

Kenney says he's always worried about safety during the city's signature large gatherings.

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"When you have the DNC for four days and you have Made in America, the Fourth of July concerts, the NFL Draft -- yeah, that keeps me up at night all the time," the mayor said.

He questions the sentiment that the Second Amendment represents an unfettered right to bear arms.

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"I'm at a loss for words to say how we can prevent this, other than keeping these kinds of weapons out of crazy peoples' hands," said Kenney.

Kenney says he thought the Sandy Hook school shooting would spur tighter gun laws, and he wonders now whether mass shootings are just the new normal.

At least 58 people were killed and more than 500 injured in the mass shooting in Las Vegas.