Tanzanian opposition party Chadema on Wednesday said three of its members were killed in incidents linked to local elections and accused the authorities of rigging the vote.
Chadema chairman Freeman Mbowe said on X that one of its candidates, Modestus Timbisimilwa, was shot dead by police in the commercial capital Dar es Salaam as he attempted to stop "fake and invalid ballots" being delivered to a polling station.
Chadema said another candidate, George Juma Mohamed, was also shot dead at his home in Mkese in central Tanzania the night before.
Police said the death occurred when a group of prison officers was called in to deal with a clash between supporters of Chadema and the ruling Chama Cha Mapinduzi (CCM) party, and fired "warning shots".
Another Chadema official, Steven Chalamila, was killed in a machete attack at his home in Tunduma near the border with Zambia, also late on Tuesday, according to the party.
"The nation has once again witnessed blatant and shameful misconduct from all levels of the government authorities, colluding to secure disgraceful victories for the CCM and its candidates, even at the cost of Tanzanian lives," said Mbowe said on X.
He said there were numerous reports of beatings and arrests of its candidates and supporters across the country as they sought to prevent the use of fake and invalid ballots.
An AFP journalist in the western city of Kigoma saw voters clashing over alleged fake ballots, leading to arrests.
"We believe these acts are being carried out with the directives and full blessings of (President Samia Suluhu Hassan) and her government," said Mbowe.
Tanzania is electing more than 80,000 local leaders, who wield considerable power in the East African nation.
It is a key test for the parties and the country's democratic institutions ahead of a presidential election next October.
"We are electing local leaders who are also important campaigners during the general election," Chadema's director of communication and foreign affairs John Mrema told AFP on Tuesday.
Hassan's CCM has been a dominant force for decades.
It has been accused of increased repression in the run-up to the vote, with Chadema saying many of its candidates were unfairly disqualified.
Hassan took office after the sudden death of her authoritarian predecessor John Magufuli in 2021.
She was initially feted for easing restrictions that Magufuli had imposed on the opposition and the media in the country of around 67 million people.
But rights groups and Western governments have criticised what they see as renewed repression ahead of the elections, with opposition politicians facing frequent arrests, as well as abductions and murder.
Chadema boycotted the last local elections polls in 2019 citing violence and intimidation, allowing a clean sweep for the CCM.