CAPE TOWN, South Africa (AP) _ A helicopter crashed into a building in the center of Cape Town early Wednesday, killing all four people aboard, police said.

The chopper had lowered an air conditioner onto the roof of the office building and was lifting off when a rotor struck a billboard, said police spokesman Capt. Mark Romburgh. The craft fell back, crashed and exploded into a fireball, he said.

The building was on a major thoroughfare and across the street from the Cape Sun, one of the city's major hotels.

Romburgh said parts of the helicopter flew off and struck the hotel, seriously damaging an unoccupied room and causing minor damage to another room. The occupant suffered no injuries.

Television footage showed the blackened roof of the building with smoke rising from the wreckage.