A FERRY HAS gone down off mainland Tanzania with about 600 people onboard –  about 380 people are believed missing.

The ferry, M.V. Spice Islanders, was heavily overloaded and some potential passengers had refused to board when it was leaving the mainland port of Dar es Salaam, said survivor Abdullah Saied.

It sank in an area with heavy currents in deep sea between mainland Tanzania and Pemba Island.

About 220 people had been rescued, said the registrar of the ship, Abdullah Mohamed. Tanzanian authorities did not yet have an official statement.

Thousands of residents mobbed the docks of Stone Town on Zanzibar, an island near Pemba, waiting for news. One man was screaming that he had lost 25 members of his family, including his sisters, his wife and grandsons. He was too upset to give his name. Many of the crowd were crying or screaming.

Seven bodies have washed up so far, said witness Abdirizak Juma.

Many of those present expressed anger that the ship had been allowed to leave port so overloaded and called on government officials to resign.

The green and hilly island of Pemba is often described as one of the best scuba diving destinations in the world.

- AP