Rescuers recovered 17 more bodies on Tuesday after a boat overloaded with religious pilgrims capsized in Bangladesh, taking the death toll to 68 as anxious relatives waited for news of several passengers still missing.

Sunday's incident near the northern town of Boda was the deadliest maritime incident in years in the South Asian country, which is crisscrossed by rivers where overcrowding on aged vessels is common.

Twenty-two of those killed were children, authorities said, with video footage suggesting some were as young as around four years old.

The small vessel was on its way to a popular temple when it flipped over in a river as onlookers screamed from the shore, in horrific scenes captured on cellphones.

Boda police chief Sujay Kumar Roy said rescue workers including firefighters, navy divers and villagers were searching for miles downstream on the Karotoa River, where the tragedy occurred.

The boat was carrying around 90 people, of whom around 50 were pilgrims on their way to the centuries-old Hindu temple for a major festival, according to police.

"The rescuers found more than a dozen bodies downstream and also under the water. Still a few more people are missing," Roy said.

Abdur Razzaque, a police inspector, said at least 30 of the dead were women.

"Among the fatalities, 67 people were Hindus and one was Muslim. We have handed over the bodies. The search has been suspended today and will resume tomorrow," he said

"A committee has been formed to probe the incident," he said, adding the country's railway minister had visited the scene to oversee rescue efforts.

Dozens of relatives of those missing were still crowding the river bank on Tuesday, although most had left after authorities handed over their family members' bodies.

"Three women of my family were missing since the boat capsized," said one distraught relative, Bikash Chandra, late on Monday.

"We found one in the morning around 10:00 am, who was rescued earlier. But I couldn't find the other two yet."

Police on Tuesday said that around 10 survivors were treated at the hospital before being sent home, police said.

District police chief Sirajul Huda said Monday the boat was carrying three times its permitted capacity.

"The boatman asked some people to disembark in an effort to ease the weight-load. But no one listened," he said.

Mobile phone footage aired by TV station Channel 24 showed the overcrowded boat suddenly flipping over, spilling the passengers into the muddy brown river.

Dozens of people watching from the shore started shouting and screaming. The weather was calm at the time.

Thousands of Hindus in Muslim-majority Bangladesh visit the famous Bodeshwari Temple every year.

Sunday marked the start of Durga Puja, a major Hindu festival drawing large crowds at the temple. (AFP)