A bomb exploded Friday outside an office of the Soviet airline Aeroflot, and officials said at least five people were injured.

An employee answering the phone at the office in downtown Geneva said the injured were passers-by and did not work in the office.Louis Ody, a spokesman at Geneva Hospital, said five victims were admitted, four of them in serious condition with leg wounds and burns.

Marcel Vaudroz, a Geneva police spokesman, said in an interview with Swiss radio that the bomb was hidden in a package left outside the Aeroflot office.

He said no one immediately claimed responsibility for the blast, and there had been no warning prior to it.