Tanzania's main opposition party said on Friday hundreds of people had been killed in protests over elections this week, as the UN secretary-general called for an investigation into allegations of excessive use of force.
The UN human rights office said credible reports indicated at least 10 people were killed in protests in three cities, the first public estimate of any fatalities by an international body since Wednesday's vote.
The foreign ministers of Britain, Canada and Norway issued a joint statement expressing concern over the situation and urging the Tanzanian authorities to act with maximum restraint and to respect the right of assembly and of free expression.
Speaking to the Reuters news agency in some of the government's first public comments on the unrest, Foreign Affairs Minister Mahmoud Thabit Kombo said the opposition's death toll was "hugely exaggerated" but that the authorities had not yet tabulated casualties. He denied that security officers had used excessive force.
But the main opposition party, Chadema, said casualties were very high.
"As we speak, the figure for deaths in Dar (es Salaam) is around 350, and for Mwanza it is 200-plus. Added to figures from other places around the country, the overall figure is around 700," Chadema spokesman John Kitoka told the Agence France-Presse news agency.
"The death toll could be much higher," he warned, saying killings could be happening during the nighttime curfew.
Protesters have taken to the streets since Wednesday, angered by the exclusion of President Samia Suluhu Hassan's two biggest challengers from the race and what they described as widespread repression.
Witnesses have said police fired tear gas and gunshots to break up some demonstrations.
Police have imposed an overnight nationwide curfew over the past two nights after government offices and other buildings were set ablaze. Internet access has been disrupted since Wednesday.
In a statement issued by his spokesperson, UN Secretary-General Antonio Guterres called "for a thorough and impartial investigation into all allegations of excessive use of force" and deplored the loss of life.
Partial election results announced on Thursday and Friday showed Hassan winning commanding majorities across the country, and complete results were expected in the coming hours.
