Zimbabwean police have arrested 39 independent election monitors working for two civil society organisations, accusing them of carrying out an illegal parallel voter tabulation exercise.

The arrests followed the extension of voting to a second day in some wards after Wednesday’s chaotic presidential, parliamentary and local government elections.

Polling stations in most urban centres failed to open on time due to non-availability of election material in a situation that sparked protests from the main opposition presidential candidate Nelson Chamisa of the Citizens Coalition for Change (CCC).

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Mr Chamisa, who is fighting to unseat President Emmerson Mnangagwa from power, said there were attempts to rig the elections in the opposition strongholds.

Police said they raided centres where monitors from Zimbabwe Election Support Network (ZESN) and Election Resource Centre (ERC) were operating from on Wednesday night.

“A raid was conducted last night (Wednesday) at Holiday Inn in Harare, at a location in Belgravia, Milton Park and also in the Grange area where several communication gadgets were recovered, which include laptops and phones,” police spokesman Assistant Commissioner Paul Nyathi said.

“Thirty-nine suspects were arrested. These were coordinating the alleged release of election results by some civic organisations, which are linked to the Zimbabwe Election Support Network, the Election Resource Centre and others.”

Rights group condemned the arrests, which they said were meant to stop voter tabulation.

“The arrest of the ZESN and ERC officials is part of a deliberate ploy by the state to target civil society organisations and ultimately silence their voice on the 2023 elections which has apparently failed to meet the credibility test,” the Crisis Coalition in Zimbabwe (CCiZ), a group of over 40 civil society groups, said.

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“This mass arrest of the ZESN and ERC observers coupled with many other electoral malpractices puts a huge dent on the credibility of this election.”

On the eve of the elections, Zimbabwe deported at least six foreign researchers from South Africa and the United Kingdom after accusing them of trying to interfere in the polls.

The government has also refused to accredit journalists from the Voice of America’s Zimbabwe’s service while local media practitioners said they were experiencing inordinate delays in getting accreditation from the electoral commission.

The United States’ Carter Centre said its observers were also being denied accreditation and that they were being demonised by the local state-controlled media.

The European Union observer mission last week said it had taken note of “unacceptable attempts to discredit” it after state-controlled media ran stories claiming that it bribed local journalists with whiskey and groceries.

President Mnangagwa, who came to power in 2017 following a military coup that toppled strongman Robert Mugabe, has been accused of trying to rig the elections where he is seeking his last term.

He previously said he had invited foreign observers because Zimbabwe had nothing to hide as it was organising a clean election.