LOUHAJONG, Bangladesh (AP) — High waves and strong currents prevented rescuers from launching a search operation Tuesday for a ferry that capsized a day earlier in central Bangladesh, leaving hundreds of passengers trapped inside and feared dead.

It was unclear exactly how many people were on board the M.V. Pinak because ferry operators in Bangladesh rarely maintain passenger lists. Authorities and survivors estimated there were about 250-300 passengers, but the figure could not be confirmed.

At least 44 passengers swam to safety after the ferry went down Monday morning, but authorities still have not launched a formal rescue operation because of choppy conditions in the Padma River, said Shipping Minister Shahjahan Khan.

In the hours after the ferry capsized, local residents in fishing trawlers and speedboats tried to reach the site but had to turn back.

A salvage ship was ready to head out once conditions improved, Khan said.

On Monday, local residents and rescuers recovered two bodies from the water, but many more were believed to be trapped inside the ferry. Many of the passengers aboard the vessel were returning from ancestral villages after celebrating Eid al-Fitr, the festival marking the end of the Islamic fasting month of Ramadan.

Scores of people die in ferry accidents every year in Bangladesh, where boats are a common form of transportation. The Padma is one of the largest rivers in the delta nation, which is crisscrossed by more than 130 rivers.

Poor safety standards and overcrowding are often blamed for the accidents. In May, about 50 people died in a ferry accident in the same district.