Tanzanian police have arrested prominent politician Tundu Lissu and two other opposition Chadema officials, the party said.
It states that the three were detained on Sunday in the city of Mbeya, in the southwest of the country, on the eve of the rally planned to mark World Youth Day.
The reported arrests come a year after President Samia Hassan lifted a ban on opposition meetings and promised to restore competitive politics.
On Sunday, police banned the Chadema demonstration, claiming the intention was to cause violence.
They cited the party’s call for people to unite as 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 he did not know where the detained leaders were being held.
The police have not officially commented on the arrests. The BBC has contacted them for comment.
Chadema spokesman John Mrema said groups of young people traveling in rented buses were arrested and forced to return to their respective regions under armed escort.
Around 10,000 young people gathered in Mbeya to celebrate youth day, with the slogan “Take control of your future”, according to the party’s youth wing.
But the police said in a statement that such gatherings would not be permitted in the city or anywhere else in the country.
Chadema authorities 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 escorted back to where they came from.
Chadema condemned the arrests, with the party president, Freeman Mbowe, demanding in a publication in X “the immediate and unconditional release of our leaders, members and supporters detained across the country”.
Lissu, who survived an assassination attempt in 2017 after being shot 16 times, returned to Tanzania last year after two years of exile in Belgium.
He returned after President Samia lifted the ban on political rallies imposed by former President John Magufuli in 2016.
The ban banned political parties from holding rallies and even engaging in internal political activities.
Samia, who came to power in 2021 after Magufuli’s sudden death, was praised for moving away from many of her predecessor’s policies.
But following the arrests, some opposition politicians criticized her, saying she is not prepared for political reconciliation.
Tanzania is expected to hold presidential and parliamentary elections late next year.
Additional reporting by Basillioh Rukanga
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