An Air France flight en route from Paris to New Delhi made an emergency landing at Sofia Airport in Bulgaria on Friday at about 5 p.m. (1500 GMT) because of a disruptive passenger, Bulgarian officials said on Saturday. The passenger, an Indian citizen, began to act up soon after take-off, quarrelling with other passengers, assaulting a flight attendant and pummelling the cockpit's door, said Ivailo Angelov, an official at the National Investigation Agency. "We are investigating both his actions and his motives," Angelov told reporters. "There is no reasonable explanation for his behaviour," Angelov said.