One of Tanzania's main opposition leaders, Freeman Mbowe, was detained by police on Friday, his Chadema party said, after officers dispersed an opposition rally with tear gas just days before local elections.
Chadema had protested earlier this week that many of its candidates had been "unfairly" disqualified from running in the November 27 polls in towns and villages across the nation.
The elections are viewed as a barometer for President Samia Suluhu Hassan, who took over in 2021 with promises of reforms and increased civic freedoms -- only to disappoint increasingly worried international observers, who point to a return to her predecessor's repressive policies.
Chadema's director of communication and foreign affairs John Mrema said on X that police had "ambushed" a party convoy in Halungu Forest in the southwest of the country.
Mrema said Mbowe and other Chadema leaders were stopped at a police roadblock, where "the police forcibly opened the car doors, assaulted those inside, and forcefully arrested them".
"The police have taken away our leaders without disclosing their destination, and we still do not know where they are being held or for what reasons," he added, urging their release.
Mrema also said that prior to his arrest, Mbowe had been blocked by police from speaking at a rally in the southern town of Mlowo.
Officers then moved in and "dispersed the gathered crowd using tear gas", according to the party.
Police confirmed the arrests, saying they were violating schedules for campaign rallies.
"Chadema leaders violated the schedule and we are holding them for grilling and investigations because some officers were injured by the opposition supporters when they were dispersing the crowd," regional police chief Augustino Senga said.
The arrests come only days after Mbowe protested over the apparent disqualification of scores of Chadema candidates hoping to run in the local polls.
The party had planned to field candidates for 65 per cent of the 80,430 posts up for grabs, but Mbowe said on Tuesday it would now only be present in about 33 per cent thanks to what he labelled "deliberate manipulation".
Ballot box test
The local polls are expected to be an indicator of the political landscape ahead of a presidential election due next October.
Hassan took office after the sudden death of her authoritarian predecessor John Magufuli in 2021 and has yet to be tested at the ballot box.
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 arrests of Chadema politicians as well as abductions and murders of opposition figures.
Only last month, Mbowe and his deputy Tundu Lissu -- as well as other opposition figures -- were briefly detained after riot police prevented a mass rally in the commercial capital Dar es Salaam.
While Chadema boycotted the last local polls in 2019 under Magufuli, citing irregularities in the nomination process, Mbowe said it would contest next week's elections.
"This time, we are not withdrawing at all. We will proceed steadily until the end," Mbowe told reporters.
"In the last five years, we have had no leadership at the grassroots. We cannot afford to stay out again."