Tanzanian police have arrested prominent politician Tundu Lissu and two other opposition members of Chadema, the party said.
According to the report, the three were arrested on Sunday in the southwestern town of Mbeya, on the eve of their planned rally to mark World Youth Day.
The reported arrests come a year after President Samia Hassan lifted a ban on opposition gatherings and vowed to restore competitive politics.
On Sunday, the police banned the Chadema demonstration, saying it was intended to cause violence.
They called the party’s call to come together, like the “youth of Kenya,” apparently referring to weeks of deadly anti-government demonstrations in the neighboring East African country.
On Monday morning, a Chadema official told the BBC they did not know where the captured leaders were being held.
Police have not yet officially commented on the arrests. The BBC has contacted them for comment.
Chadema spokesman John Mrema said groups of youths travelling in hired buses were arrested and sent back to their region under armed escort.
According to the party’s youth wing, about 10,000 young people would gather in Mbeya to celebrate Youth Day, with the slogan: “Take control of your future”.
But the police said in a statement that such gatherings would not be allowed in the city or elsewhere in the country.
Chadema officials shared photos of a large group of about 100 party members who they said were detained in Iringa, a town near Mbeya. They were later released and returned to where they came from.
Chadema has condemned the arrests, with party chairman Freeman Mbowe in a message on X demanding “the immediate, unconditional release of our leaders, members and supporters arrested across the country”.
Mr Lissu, who survived an assassination attempt in 2017 after being shot 16 times, returned to Tanzania last year after two years in exile in Belgium.
He returned after President Samia lifted a ban on political gatherings imposed by the former president. Chairman John Magufuli from 2016.
The ban prohibited political parties from holding meetings and even engaging in internal political activities.
Ms Samia, who came to power in 2021 after the sudden death of Mr Magufuli, was praised for distancing herself from many of her predecessor’s policies.
But after her arrests, some opposition politicians have criticized her, saying she is not ready for political reconciliation.
Tanzania will hold presidential and parliamentary elections at the end of next year.
Additional reporting by Basillioh Rukanga
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