At least four killed in US school bus collision

A school bus carrying foreign exchange students collided with a tour vehicle in the US West Coast city of Seattle, killing at least four people and critically injuring 12 others, officials said. Melissa Mixon, spokeswoman for North Seattle College, told AFP that 45 foreign exchange students and staff with the school's international program were on board the bus. "The accident occurred when a charter bus traveling with the students collided with a 'Ride the Ducks' tour vehicle," Mixon said.