A bus plunged into a ravine in Indonesia's Sumatra island on Tuesday, killing 10 passengers and injuring 20, police told domestic media. Elshinta news radio, quoting police officials, said the bus was carrying 48 people when it plunged into a 300-metre deep ravine in Sumatra's Lampung province, about 250 km (155 miles) northwest of the capital Jakarta. "Two died on the spot, 20 were heavily injured and eight people died on the way (to hospital)," the police officer, who did not give a name, told Elshinta. He said rescue officials were still searching for the remaining passengers. The cause of the accident was not known.