A boat overcrowded with about 150 picnic guests capsized on a vast reservoir in India's eastern Orissa state and at least 22 people drowned, officials said Monday.

Scuba divers with flashlights were searching for 10 other people who were still missing, though there was little chance of finding survivors a day after the boat sank Sunday, Deputy Relief Commissioner Prabat Ranjan Mahapatra said.

Police, firefighters and emergency workers pulled dozens of survivors from the water, state official Pradeep Kumar Mahapatra said.

Survivors said the boat was carrying people back from a picnic on the opposite banks of the Hirakud reservoir, a 55-kilometer (34-mile) -long reservoir created by the Hirakud Dam in the Mahanadi River in Sambalpur District, about 1,300 kilometers (800 miles) southeast of New Delhi.

Authorities were investigating the accident, though they believe overcrowding was a likely cause. They had no information on the boat's capacity.