A ferry with at least 280 people on board has sunk off the east African coast of the Zanzibar archipelago, killing at least 31 people, including some foreigners, the government has said.
Dozens of people were missing after the ferry, MV Kalama, capsized after it set sail from the Tanzanian commercial capital of Dar-es-Salaam around midday on Wednesday, officials said.
"We have so far received 24 bodies, including two Europeans," Hamad Masoud Hamad, Zanzibar's transport minister, told journalists gathered at the main hospital after the sinking of the MV Kalama.
This was the second such ferry disaster in Zanzibar, a semi-autonomous part of Tanzania, in less than a year.
"The rescue operations are continuing... 124 people have already been found alive and we hope that others will be saved," Emmanuel Nchimbi, Tanzania's interior minister, said.
Rescue boats and divers were searching for any remaining survivors on the mostly submerged vessel.
Government spokesman Yusuf Chunda said 13 foreigners were rescued and are in hospital. It was not clear how many other foreigners had been on board.
"More than 200 people are believed to have been on board the boat when it capsized. We don't know how many of them sank with the boat," Zanzibar police spokesman Mohammed Mhina said.
"The rescue operation is ongoing as we speak but almost the entire boat has been submerged in water ... only a small part of the boat is now visible."
An AFP journalist at the port on the main island of the Indian Ocean archipelago said he had seen 55 survivors, soaking wet, on the quayside.
Medical personnel were handing out blankets as the survivors emerged from rescue boats, before being sent to a nearby hospital. Some unconscious victims were being carried on stretchers.
It was not fully clear what caused the accident, but preliminary reports indicated the vessel may have capsized after being hit by strong winds and waves, Mhina said.
Police said the vessel was carrying 250 adult passengers and 31 children when it capsized near Chumbe Island, west of Zanzibar.
The ferry is owned by a company named Seagull, which also runs a number of other ferries. Previous reports had indicated the vessel was called MV Salama.
More than 200 people perished in September when the ferry Spice Islander capsized while sailing between two of the three islands that make up Zanzibar, in one of the worst maritime disasters in Africa in the past decade.