Rescue efforts are underway in Thailand after an overcrowded ferry sank near the Thai seaside resort of Pattaya.

Police say the ferry sank because of engine problems.

At least six people were killed.

Two Russians, three Thais and one Chinese person are among the dead.

The shuttle ferry is reported to have been carrying approximately 200 passengers -- despite a capacity limit of 150.

Eyewitnesses told police that the ferry was not equipped with enough life-jackets and some of the passengers could not swim.