More than 90 people have been killed in landslides in southeast Bangladesh after three days of rains that triggered flash floods and severed transport links, officials said Wednesday.

The army has been deployed to help with rescue efforts in the affected hill region of Chittagong, said the region's chief administrator, Sirajul Haq Khan, who warned that the death toll could rise as more remote areas are accessed.

According to Khan, at least 94 people died in a series of landslides and flash floods in and around Chittagong port and the neighbouring districts of Cox's Bazar and Bandarban.

Bandarban administrator Tariqul Islam said 36 bodies have been recovered from multiple landslide sites.

"Rescue efforts had been hampered as communications have been largely snapped because of flash floods and heavy rain," Islam told AFP.

"Ten of the victims were children and scores of others were injured," he said.

According to Bandarban police chief Saiful Ahmed, most of the victims were asleep when the huge chunks of mud buried them alive.

"One family has lost 12 members," he added.

Officials in Cox's Bazar said at least 37 people had been killed there.

Thousands of poor people in the region live in shanty houses at the foot of the hills, defying repeated warnings from authorities about the danger of landslides, which are common during the monsoon season.

"We try to relocate them in safer places, but they do not want to leave their belongings," Khan said.

Chittagong port received 40 centimetres (16 inches) of rain in a single 12-hour period on Tuesday and fire department officials said rescuers were working under the constant threat of further landslides.

Flights in and out of Chittagong's Shah Amanat International Airport have been suspended since Tuesday afternoon.

According to the state Disaster Management Information Centre, around 50,000 people were affected by the flash floods, and many of them forced to take shelter on higher ground.

Train links between Chittagong and the rest of the country were also severed after a railway bridge collapsed due to a rain-triggered flash flood.

In recent years, monsoon rains have caused deadly landslides in Chittagong, home to five million people, killing hundreds and prompting the government to tighten rules on where development can take place.

In June 2007, landslides in Chittagong killed at least 130 people. Another 53 were killed by flash floods and landslides in Cox's Bazar district in 2010.