Police and soldiers deployed in force in Tanzania's commercial capital, Dar es Salaam, on Tuesday to try to prevent protests called for by activists to denounce the violent suppression of demonstrations around elections in October.

The government said any protests on Tuesday, the anniversary of mainland Tanzania's independence from Britain in 1961, would amount to a coup attempt and urged people to stay at home. 

Presidential and parliamentary elections on October 29 triggered the worst political violence in Tanzania's post-independence history. The United Nations (UN) has estimated that hundreds were killed. 

The police and army were patrolling major streets in Dar es Salaam and checking the identification of anyone seeking to move around, residents told Reuters.

They said the situation appeared calm as of late morning, although one resident and some activists on social media said small protests had begun in some parts of the city. This could not be immediately confirmed. 

A police spokesperson did not respond to a request for comment. 

Samia Suluhu Hassan won a new term in the election with nearly 98% of the vote after leading opposition candidates were barred from running.

She appointed a commission last month to investigate election-related violence but has repeatedly denied that security forces acted improperly.

UN human rights experts said last week at least 700 people were estimated to have been extrajudicially killed in the violence.

The government has acknowledged that people died but has not provided its own death toll.

The United States said last week it was reviewing its relationship with Tanzania over concerns about violence against civilians as well as religious freedom, free speech and barriers to investment.

In the months leading up to the elections, opposition leaders and human rights activists accused the government of being behind the disappearance of dozens of its critics.

Hassan said last year that she had ordered an investigation into reported abductions, but no results have been announced.