(KRON) —  The man who killed 58 people and injured at least 515 others at a Las Vegas concert was a retiree with no criminal history in the Nevada county where he lived, police said Monday.

The brother of Stephen Paddock, 64, said he’s “completely dumbfounded” by the shooting at a country music concert Sunday night, the deadliest in modern U.S. history. Eric Paddock told the Orlando Sentinel newspaper that he can’t understand what happened.

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