Tanzania's main opposition Chadema party on Friday said that around 700 people had been killed in election-related violence since Wednesday's poll.

The party was barred from competing in the election and said protesters were again taking to the streets of the East African country's financial capital, Dar es Salaam.

Crowds took to the streets in cities around the country after the election, with police and protesters clashing, leading to a nighttime curfew.

Internet access has been intermittent since Wednesday as the nation awaits official results. 

What Tanzania's opposition Chadema party said

"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 AFP news agency.

"The death toll could be much higher," Kitoka warned, adding that killings could be taking place during the overnight curfew.

The UN human rights office expressed alarm over the deaths and injuries in the election-related unrest and said it had reliably learned of at least 10 deaths.

"Credible reports we have received indicate that at least 10 people were killed in Dar es Salaam, Shinyanga and Morogoro as the security forces used firearms and tear gas to disperse protesters," spokesperson for the UN High Commissioner for Human Rights Seif Magango said in a statement.

The UN human rights office went on to call for security forces to stop using "unnecessary or disproportionate force, including lethal weapons, against protesters" and added that "protesters should demonstrate peacefully."

Tanzanian Foreign Minister Mahmoud Thabit Kombo told al-Jazeera on Friday that "no excessive force" has been used against protesters. He added that the government had "no figures" on the number of dead. 

Tanzania's one-horse election race

President Samia Suluhu Hassan of the Chama Cha Mapinduzi (CCM) party went into the election to secure a second term in office virtually unopposed. The Chadema party boycotted the poll after its leader, Tundu Lissu, was imprisoned.

The other opposition contender, Luhaga Mpina from the Alliance for Change and Transparency (ACT-Wazalendo), was disqualified by the Independent National Electoral Commission.

Sixteen opposition candidates representing smaller parties were on the ballot but were not expected to be a challenge to Suluhu Hassan.

Edited by: Sean Sinico