A device left in a casino parking garage exploded early Monday, killing a man who tried to pick it up off the top of his car, authorities said.

The device exploded shortly after 4 a.m. on the second floor of a parking garage behind the Luxor hotel-casino, said Officer Bill Cassell, a police spokesman. He declined to describe the device, but said initial reports that it was inside a backpack were wrong.

The blast was not a terrorist act but an apparent murder of a man who worked at a business inside the hotel, he said, adding that the case was being investigated as "a homicide with an unusual weapon."

No threat had been made against the Luxor, Cassell said.

"We believe the victim of this event was the intended target," Cassell said. He said another person who was with the man narrowly escaped injury.

Gordon Absher, a spokesman for MGM Mirage Inc., which owns the Luxor, said the victim was not a company employee.

Aerial video showed no apparent damage to the parking structure, where entrances were blocked while police, firefighters and federal Bureau of Alcohol, Tobacco, Firearms and Explosives agents investigated.

There was little damage around the vehicle and the hotel was not evacuated, police and a hotel official said.

Immediately after the explosion, entrances were sealed and authorities went vehicle to vehicle with bomb-sniffing dogs.

Later, people were allowed to remove their vehicles after an inspection, Absher said.

The Luxor, a pyramid-shaped hotel at the south end of the Las Vegas Strip, has more than 4,000 rooms and 6,000 employees.