Rescuers were frantically searching for survivors Saturday after an overloaded ferry sank in rough waters off the coast of western Myanmar killing more than 30 people and leaving at least a dozen more missing.

The "Aung Takon 3" went down late Friday after leaving the town of Kyaukphyu on its way to Sittwe in western Rakhine state, police said.

"The latest death toll is 33 -- four men including a monk and 29 women. At least 12 persons are still missing," a police officer in Sittwe town told AFP, speaking on condition of anonymity.

He added 169 people had now been rescued, and that no foreigners were believed to be on board the ship.

"We suspect that the boat sank because it was overloaded with goods," the police officer said, adding that the ship was listed as carrying 214 passengers and crew.

But locals said they feared the ferry was packed with unregistered ticket holders who would not have shown up on the ship's manifest, a common practice on the impoverished nation's often overcrowded ferry network.

"We don't know how many are still missing because some people were on board without official tickets," Hla Shwe, a local from Ngaputhone village, which lies a few kilometres (miles) away from where the ship went down, told AFP by telephone.

"There are many dead bodies which didn't appear yet," local MP Maung Lone added, also by telephone. "We estimate about 300 people were on board."

Three navy boats and a host of private vessels were sent to scour the area after news emerged that the ferry had sunk shortly after 8.30 pm (1400 GMT).


Treacherous waters

Many Myanmar citizens living along the nation's lengthy coastline and flood-prone river systems rely heavily on poorly-maintained ferries for transportation.

Sinkings are not uncommon. Ten people were killed in 2010 when a ferry capsized in the Irrawaddy delta region, while 38 perished in 2008 when a ship went down in the Yway River.

Locals said the area where the "Aung Takon 3" capsized was notorious for its treacherous waters.

"The tide there is very strong and the sea very rough. Fishing boats have often sunk in that area many times before," Sittwe town resident Thein Zaw told AFP.

In recent years Rakhine state has also been the departure point for thousands of desperate Muslim Rohingya who crowd onto small and dangerously overcrowded boats to escape persecution, often aiming for Thailand and Malaysia.

Communal violence between Buddhists and Rohingyas swept through the region in 2012 leaving at least 200 dead.

Some 140,000 people, mainly Rohingya, are trapped in miserable displacement camps around Sittwe after losing their homes in the unrest.

Referred to by the government as "Bengali", they are largely seen as illegal immigrants from Bangladesh, even if many can trace their ancestry in the country back for generations.

The Arakan Project, a rights group monitoring departures, estimated in October that some 100,000 Rohingya are thought to have fled by boat since 2012.

Many of those vessels are barely seaworthy and some are known to have never reached their destination.