A Bulgarian air safety official misunderstood a radio code and put out a false alarm that a Lufthansa jetliner had been hijacked after taking off from Izmir, Turkey, a spokesman for the West German airline said. The official misunderstood the routine code transmitted by a pilot when a plane enters foreign territory, the spokesman said. The official then alerted the Lufthansa office in Frankfurt, causing the false alarm. The Lufthansa spokesman also denied assertions by West German and Turkish officials that the pilot had pushed "the wrong button." "No button was pushed at all," the spokesman said.