Rescuers have found eleven people dead and kept searching dozens others who are missing after a wooden ship sunk in East Nusa Tenggara province in eastern parts of Indonesia on Monday, rescuer said.

Head of Rescue Office in the province Hermanto da Gomes said that the ship sunk at 09:30 local time at waters of Lewoleba after leaving from Bolang village of the province.

The searching of the missing persons by the rescuers, helped by fishermen, police and those from the government office, are under way, he said, adding that 17 people have been evacuated and rushed to nearby hospitals.

According to the manifest, there were 60 people on the ship. But it was believed that more people were on it, said Gomes.

"The number of people on board is more than the manifest, as it has been common," he told Xinhua over phone from the province.

"It was not clear the cause of the accident, as it took place during a favorable weather condition," Gomes said.

Sea accident often happened in Indonesia due to lack of safety standard.