The captain of an overloaded ferry that capsized on Lake Victoria has been arrested as Tanzania mourns more than 200 people killed in the latest maritime disaster in the East African nation.

Although hopes were fading of finding any more survivors by day three of the search effort, workers rescued an engineer who had managed to locate a pocket of air in the vessel.

Four navy divers heard sounds that suggested signs of life early on Saturday. They pulled the man out of the overturned ship and he was rushed to hospital.

The man shut himself into the engine room and found an air pocket that managed to keep him alive, the Tanzanian Broadcasting Corporation reported. His condition wasn't immediately known.

Bodies continued to float to the surface around the vessel on Saturday. The death toll rose to 209, public radio reported.

While the cause of the accident was not immediately clear, overloading is frequently to blame for such incidents. The vessel's capacity was said to be 100 but state television, citing witnesses, reported more than 200 people were aboard the ferry.

Tanzanian President John Magufuli had on Friday ordered the arrest of ferry management.

Transport and Communication Minister Isack Kamwelwe said the government had started sending sophisticated equipment to aid the recovery effort.

“This equipment will increase efficiency in the rescue operation and we will continue with the search until we are satisfied that we have rescued everyone,” he told Reuters news agency.

Relatives of the deceased have started to identify the bodies of their loved ones

Meanwhile the president has declared four days of national mourning and said the government would cover the funeral expenses of the victims.