Rescue efforts are underway in Thailand after an overcrowded ferry sank near the Thai seaside resort of Pattaya.<br/> <br />Police say the ferry sank because of engine problems.<br/> <br />At least six people were killed.<br/> <br />Two Russians, three Thais and one Chinese person are among the dead.<br/> <br />The shuttle ferry is reported to have been carrying approximately 200 passengers -- despite a capacity limit of 150.<br/> <br />Eyewitnesses told police that the ferry was not equipped with enough life-jackets and some of the passengers could not swim.