COTABATO: Twelve people were killed late on Tuesday and at least 42 injured in a bomb blast in southern Philippines, officials and police said. The bomb exploded in the town of Makilala on the southern island of Mindanao during a celebration to mark the town's 52nd anniversary, said Mayor Honofre Respicio. No one claimed responsibility for the blast.Earlier on Tuesday four people were injured when a bomb planted by suspected Muslim extremists exploded in the busy market of Tacurong City, just 50 kilometres from Makilala, North Cotabato province.