Tanzania political opposition says 700 people killed amid unrest over election that excluded leader's foes

Around 700 people have been killed in three days of election protests in Tanzania, the main opposition party said Friday, with protesters still on the streets in the midst of an internet blackout. 

President Samia Suluhu Hassan had sought to cement her position and silence critics in her party with an emphatic win in Wednesday's election, in which her main challengers were either jailed or barred from standing.

But the vote descended into chaos as crowds took to the streets of Dar es Salaam and other cities, tearing down her posters and attacking police and polling stations, leading to an internet shutdown and curfew.

With foreign journalists largely banned from covering the election and a communications blackout entering its third day, information from the ground has been scarce.

The main opposition party, Chadema, said clashes continued between protesters and security forces in the commercial hub on Friday.

"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 French news agency AFP.

"The death toll could be much higher," he warned, saying killings could be happening during the nighttime curfew.

A security source told AFP they were hearing reports of more than 500 dead: "Maybe 700-800 in the whole country."

"We are talking hundreds of deaths," a diplomatic source told AFP.

The United Nations said "credible reports" indicated 10 dead, in the first information released by an international body.