JAKARTA, Oct. 8 -- A boat with dozens of people on board has sunk in East Java province of western parts of Indonesia, leaving 7 persons missing, an official of disaster agency said earlier Saturday.

Overloading was blamed for the incident, which took place in Bengawan Solo river situated in the border of Lamongan and Tuban districts on Friday, Sutopo Purwo Nugroho, spokesman of the disaster management agency told Xinhua via phone.

Rescuers have evacuated safely 18 people and are searching for 7 others, he said.

Low visibility in the deep water has hampered the search and rescue operation, Sutopo added.

Boat is a favorite transport means in Indonesia, but lacking safety standards often trigger accidents.