Tanzanian President Samia Suluhu Hassan has been sworn in for a second term amid tight security, following an election marred by violent protests and rejected by the opposition as a sham.

The inauguration ceremony is being held at a military parade grounds in the capital, Dodoma, instead of a stadium as in previous years. It is closed to the public but is being shown on state TV.

Samia was declared the winner on Saturday with 98% of the vote. She faced little opposition with key rival candidates either imprisoned or barred from running.

International observers have raised concerns about the transparency of the election and its violent aftermath, with hundreds of people reportedly killed.

The authorities have sought to downplay the scale of the violence. It has been difficult to obtain information from the country or verify the death toll, amid a nationwide internet shutdown in place since election day.

Wearing a red headscarf and dark glasses, Samia took her oath of office at a ceremony attended by regional leaders and dignitaries, including the presidents of Somalia, Zambia, Mozambique, and Burundi. State broadcaster TBC had earlier said the public would not attend the event.

In her victory speech on Saturday, Samia said the poll was "free and democratic" and described the protesters as "unpatriotic".

Opposition leaders and activists say hundreds were killed in clashes with security forces. The opposition Chadema party told the AFP news agency that it had recorded "no less than 800" deaths by Saturday, while a diplomatic source in Tanzania told the BBC there was credible evidence that at least 500 people had died.

The UN human rights office earlier said there were credible reports of at least 10 deaths in three cities.

Following the unrest, the prices of food, fuel and other essentials have more than doubled or tripled in many areas. Schools and colleges are closed and public transport is halted.

Chadema - which was barred from competing - rejects the results announced by the electoral commission, saying they had "no basis in reality as the truth is that no genuine election took place in Tanzania". It has called for a fresh election.

On election day, polling stations remained largely empty - but the electoral authorities later said turnout had been 87%.

On Sunday, police spokesman David Misime blamed motorbike operators and foreign nationals for the violent demonstrations and vandalism.

He said there were individuals who had "entered the country illegally with the intention of causing chaos".

Misime has urged Tanzanians to report "any foreigner who is unknown or whose activities in Tanzania are unclear" to the authorities.

His remarks come amid reports that several Kenyan nationals have gone missing in Tanzania. Kenyan activist Hussein Khalid said on X that he had received reports of a Kenyan teacher being killed and others still unaccounted for.

The situation in Tanzania has sparked global concern, with Pope Leo XIV on Sunday calling for prayers, saying post-election violence had erupted "with numerous victims".

EU foreign affairs chief Kaja Kallas urged Tanzanian authorities to exercise restraint to preserve lives, while UN Secretary-General António Guterres said he was "deeply concerned" about the situation "including reports of deaths and injuries".

The country's two main opposition leaders did not contest the election - Tundu Lissu is being held on treason charges, which he denies, while Luhaga Mpina of the ACT-Wazalendo party was excluded on legal technicalities.

Sixteen fringe parties, none of whom have historically had significant public support, were allowed to run.

The ruling party, Chama Cha Mapinduzi (CCM), and its predecessor Tanu, have dominated the country's politics and have never lost an election since independence.

Ahead of the election, rights groups condemned government repression, with Amnesty International citing a "wave of terror" involving enforced disappearances, torture, and extrajudicial killings of opposition figures.

The government rejected the claims, and officials said the election would be free and fair.

Samia came into office in 2021 as Tanzania's first female president following the death of President John Magufuli.