A river ferry carrying up to 140 passengers capsized in central Bangladesh on Sunday after being hit by a cargo vessel, killing at least 48 people, officials said. A rescue operation was underway, but it was not clear how many people were missing.

The ferry was struck by the cargo vessel at the Daulatdia-Paturia crossing on the Padma River on Sunday afternoon, said fire department official Shahzadi Begum. Rescue teams were deployed and passing boats were helping in the operation, she said.

The site is 25 miles northwest of Dhaka, the capital. Ferry accidents are common in Bangladesh, an impoverished South Asian nation that is crisscrossed by more than 130 rivers.

The ferry, the M.L. Mosta, was submerged at a depth of up to 20 feet, said Inspector Zihad Mia, who is overseeing the rescue operation.

By Sunday evening, at least 48 bodies had been recovered, Mia said.

He said officials had yet to determine how many passengers were missing. Ferries in Bangladesh usually do not maintain formal passenger lists.

"We don't have a clear picture about how many were exactly in the ferry when it sank," Mia said. "But I think many have survived."

Jewel Mia, an official from the Bangladesh Inland Water Transport Authority, told reporters at the scene that up to 140 people were on board when the ferry sank.

A passenger who survived said many people got trapped inside when the ferry sank. "The passengers who were on the deck have survived, but many who were inside got trapped," Hafizur Rahman Sheikh was quoted as saying by the Prothom Alo newspaper.

Sheikh said the cargo vessel hit the middle of the ferry.

Authorities ordered an investigation into the accident and a five-member committee has been asked to submit a report within 15 days, the Ministry of Shipping said in a statement.

The Padma is one of the largest rivers in Bangladesh, where overcrowding and poor safety standards are often blamed for ferry disasters.

Last August, a ferry with a capacity of 85 passengers was found to be carrying more than 200 when it capsized on the Padma near Dhaka, leaving more than 100 people dead or missing. The ferry's owner was arrested after weeks in hiding on charges of culpable homicide, unauthorized operation and overloading.

At least five people were killed earlier this month when a ferry sank in southern Bangladesh.