STONE TOWN, Zanzibar (Reuters) - Nearly 200 people drowned when an overloaded ferry capsized off east Africa as it sailed from Zanzibar to Pemba island, police said on Saturday, Tanzania's worst maritime disaster in at least 15 years.

Fishing boats, tour operators and diving instructors spent the night scouring the sea off the coast of Tanzania looking for survivors, many clinging to strewn cargo. One photo showed two men and a child floating on a mattress, clinging to a fridge.

Zanzibar police spokesman Mohamed Mhina told Reuters 192 bodies had been recovered and 606 passengers rescued from the Indian Ocean so far.

"There is a possibility that more bodies still remain at sea. Rescue workers are still searching for survivors and retrieving bodies," he said.

Two tug boats docked at Zanzibar's port, one carrying 17 bodies and another with 15 bodies, many of them children.

At the northern tip of the island, dozens of soldiers carried bodies onto white sand beaches, where thousands of people anxiously awaited news of survivors.

"The ferry flipped and capsized. There could be more bodies trapped inside the hull of the ship with the cargo," rescue worker Ali Ramadhan told Reuters at the port. "We suspect the ship was overcrowded with more than 800 passengers onboard. It is normal for these ferries to overload passengers and cargo."


Zanzibar Police Commissioner Mussa Alli Mussa said early on Saturday that more than 500 people were on the ship's manifest. Abdual Said, registrar of Zanzibar's seafaring vessels, said the MV Spice Islander was licensed to carry 600 passengers.

The vessel had been sailing from Zanzibar to Pemba, the two main islands of the Zanzibar archipelago, a semi-autonomous region of Tanzania and popular beach destination for tourists.

Rescue worker Ramadhan said a lack of equipment was hampering rescue operations.

"A helicopter helped to rescue some survivors but with the high tide coming in some of the bodies could drift as far as (the Kenyan port city of) Mombasa," Ramadhan said.

A stream of military trucks brought in bodies to the Maisara football grounds in Zanzibar's main city, where tens of thousands of people gathered to identify the dead.

Emergency workers covered bodies in dark blankets and placed the victims' clothes on top so relatives could identify them.

Hundreds of people gathered outside the main Mnazi Mmoja Hospital where medical workers read out the names of survivors and posted lists on hospital walls.

"We are still receiving many bodies by truck loads ... The death toll will likely be much higher," doctor Karim Zah of the Mnazi Mmoja Hospital in Zanzibar told Reuters.

At the tourist destination of Nungwi at the northern tip of Zanzibar, fishing boats and diving vessels ferried survivors ashore. Crowds waded waist deep into the water as the boats approached, desperately seeking relatives.

"Many of us got here about 2.30 a.m. (2330 GMT) this morning," said Suleiman Amis, 32, who works on a local diving tour boat. "We sent out some boats to search for the survivors, but we did not find them until very, very late."

"We have friends who we know took that boat and we want to go back out to find them as soon as possible," he told Reuters.

Pemba is about 40 km (25 miles) from Zanzibar. Passengers who regularly take ferries between the two islands said the vessels are in a poor state and often overcrowded.

"They normally pack us in like sardines in a can. And for that I really fear this could be a very big disaster," said resident Mwnakhamis Juma.

A parent in Mkoani on Pemba island was already mourning his three children who were aboard. "I had two sons and a daughter coming back to Pemba from a school holiday break ... I am fearing for the worst," said Juma Bakar.

The government announced three days of mourning and Tanzanian President Jakaya Kikwete postponed a trip to Canada.

The government in Zanzibar said last month it planned to invest in bigger, more reliable vessels to ferry passengers between the two islands.

"We are fearing the greatest calamity in the history of Zanzibar. This is a disaster," said a government official, who declined to be named.

Tanzania's worst maritime disaster was in May 1996 on Lake Victoria. The MV Bukoba ferry sank with as many as 1,000 people on board. Only 114 passengers survived and the captain and eight officials were charged with the murders of 615 people.

Two small overloaded boats capsized and were swept away in high seas off Tanzania's coast in January this year. In May 2009 a vessel just off Zanzibar sank with dozens aboard, killing six.

(Additional reporting by Marton Dunai in Nungwi, Zanzibar; Writing by David Clarke and Yara Bayoumy; Editing by David Clarke)

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