Indonesian rescue workers searched Tuesday for six missing passengers after their boat sank in rough seas off the eastern coast of central Sumatra, DPA quoted local media as saying. Three people were killed and five others were rescued after the accident, which took place on Monday morning when the small wooden boat, carrying 14 people, turned over and sank in eastern coast of Riau province in eastern Sumatra. Adjunct Senior Commissioner Agus Sarjito, police chief of the Rokan Hilir district, said the boat was en route to Kubu sub-district from Sungai Daun village. After about four hours into the journey, the boat was hit by huge waves and sank immediately, Sarjito told the Jakarta-based Elshinta private radio. The boat's captain and four other passengers survived in the accident after being picked up by fishing boats, he said, adding that search continued Tuesday for the six missing persons, who were feared drowned.