Kuala Lumpur - Ten people are confirmed dead and about 30 missing after a boat believed to be carrying Indonesian illegal immigrants capsized in rough seas off Malaysia, officials said on Monday.The bodies of six women and four men were washed ashore at a beach near the east coast town of Mersing earlier Monday, the Malaysian Maritime Enforcement Agency said."We believe there were about 40 Indonesians on the boat and we believe they were illegal immigrants," an agency spokesperson said.The boat was headed from Indonesia to Malaysia when it capsized. Two passengers were rescued and taken to hospital but their condition was unknown.A search is underway for the missing.The agency said the craft probably sank because it was overloaded and hit by rough seas. No further details were provided but such accidents are common. Last November a speedboat believed to be carrying illegal Indonesian migrant workers returning from Malaysia sank near Batam Island, south of Singapore. More than 40 people were missing.