Eleven missing in shipwreck off Sumatra

At least 11 people are missing after a boat sank off the island of Sumatra in western Indonesia, the local relief agency said Tuesday.

According to the agency, the shipwreck occurred on Monday at around 11:00 am (5:00 am in Lisbon) while the vessel was near the Mentawai Islands, an archipelago located off the west coast of Sumatra.

"We are focusing on searching the area around the estimated crash site to find all the victims," said rescue leader Rudi, who, like many Indonesians, goes by one name. Seven of the 18 passengers on the boat have already been found.

Maritime accidents occur regularly in Indonesia, a vast archipelago of some 17,000 islands, in part due to lax safety regulations.

Earlier this month, a ferry carrying 65 passengers and crew capsized off Bali, killing at least 18 people. In March, a boat carrying 16 people capsized due to rough seas, also off the tourist island of Bali. One Australian woman died and at least one other person was injured.