Tanzanians will go to the polls on November 27 in the first real political test of President Samia Suluhu Hassan's administration.

The official date was announced this week as security agencies and the main opposition party, Chadema, clashed over the right to assemble, which the authorities saw as a plot to sow chaos in the country.

Hopes for a smooth conduct of the civic poll, which will lay the groundwork for next year's general elections, were dealt a severe blow after a heavy-handed police response to Chadema's plan to hold a rally in Mbeya, south-west Tanzania. 

The party's leaders and some supporters, more than 500 of them, were arrested ahead of the rally on Monday before being released and sent back to their homes.

The incident overshadowed the long-delayed announcement of the election date by the Ministry of Local Government and Regional Administration (Tamisemi), which was made with fanfare in the capital Dodoma on Thursday.

Police violently enforced a ban on the opposition rally, which was to mark the annual International Youth Day.

Among those arrested in the raid were party Chairperson Freeman Mbowe, Vice-Chairperson Tundu Lissu, Secretary-General John Mnyika and central committee member Joseph Mbilinyi, who were eventually taken back to their home regions under heavy police guard with other detainees.

The police and the Office of the Registrar of Political Parties said they were concerned that the rally could spark anti-government protests along the lines of the Gen-Z youth movement in neighbouring Kenya as the reason for prohibiting it.

But at their first press conference on Wednesday after returning to Dar es Salaam, the Chadema leaders condemned the "unprecedented brutality" they had experienced at the hands of the police.

Lissu and Mnyika minced no words in describing how police officers used batons, pepper spray and tasers to rough them up, and how their colleague Mbilinyi was seriously injured and taken to hospital in Dar es Salaam.

Mnyika recounted how the police team leader, Commander (CP) Awadh Haji, who heads the force's Operations and Training Unit, "snatched my spectacles off my face, broke them and then stomped on them, before other police officers began beating us up mercilessly".

"We were then thrown into police trucks and driven for hundreds of kilometres, lying face down. Mbilinyi in particular was in a very bad state," he added.

Mbowe said the police action was "totally uncalled for" and said it was a deliberate strategy to cripple the opposition ahead of Tanzania's new election season.

"Instead of achieving their intended purpose of deterring the youth from pursuing the kind of mutinous stances we have seen in Kenya, Uganda, Nigeria and elsewhere, such actions could actually spur them on. And it would be pointless to blame the opposition [if this were to happen]," the party leader said.

He said that despite the incident, Chadema would continue its quest for political equality and that if such police violence was repeated in either of the two upcoming elections, "this country will not be safe for anyone".

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The party has also announced its intention to take legal action against CP Haji and Assistant Registrar Sisty Nyahoza, who signed the letter to Chadema banning the Mbeya rally, in their personal capacities for spearheading the week's events. 

Mr Nyahoza's letter quoted invitation videos posted on social media by the party's youth leaders calling on youths across the country to attend the rally "to show that they are as serious as their Kenyan counterparts in charting a new destiny for the country and doing away with state control".

He said such statements were tantamount to inciting social chaos, which Mbowe dismissed as a "completely baseless assumption".

The nationwide November 27 civic poll will see the election of village, street and ward chairpersons and council members.

It is expected to be a litmus test for the 2025 presidential and parliamentary elections, in which the ruling CCM party will seek to maintain its legislative dominance and President Samia Suluhu Hassan will seek to secure an outright electoral mandate for the first time.

She was elevated from vice-president by constitutional decree after her predecessor John Magufuli died in office in 2021.

However, the Mbeya incident has fuelled scepticism about the chances of a free and fair vote in November, especially as questions have also been raised about the government's continued oversight of local elections, despite the establishment of an Independent National Electoral Commission (INEC) following amendments to the electoral law earlier this year.

Kicking off the November race on Thursday, Tamisemi Minister Mohamed Mchengerwa, whose portfolio falls directly under the president's office, said ballot papers and other required documents were ready for the exercise.

Contesting political parties will only be allowed to start formal campaigning a week before the polls on November 20, and have also been instructed to submit their campaign meeting schedules to the ministry's approved election supervisors at least a week in advance.