Secret footage filmed by a Zimbabwean prison guard shows how a supporter of President Robert Mugabe rigged votes in his favour.
The hidden camera images apparently show one of Mugabe's so-called war veterans - with the power to denounce prison workers as opposition supporters - supervising their votes, logging each one against the voter's identification number and watching as they mark the ballots.
"It is believed to be the first footage of actual ballot-rigging," British newspaper The Guardian said.
Harare prison guard Shepherd Yuda, 36, who filmed the clips, has since fled Zimbabwe with his pregnant wife and their children.
The 10 minute film is on the British daily's website. It was filmed during the six days before the June 27 presidential election second round run-off.
The Guardian gave Yuda the camera to film the daily life of a prison guard but he found himself recording the overseeing of ballots by supporters of Mugabe's ZANU-PF ruling party.
Tendai Biti, the number two in the main opposition Movement for Democratic Change, is seen in prison having leg irons taken off him before going to court to face treason charges.
MDC leader Morgan Tsvangirai pulled out of the election, saying violence and intimidation against his supporters made a free and fair vote impossible. Though Tsvangirai remained on the ballot paper, Mugabe was the only candidate.
The film said a big meeting was suddenly called at the prison. Top-ranking officials from the prison service arrived to tell the prison officers who to vote for. Attendance was compulsory.
One man addressing the crowd says: "Forward with ZANU-PF! Forward with ZANU-PF! Down with MDC!"
Another then tells the prison workers: "Tsvangirai, even if you vote for him, even if he wins he will never rule this country. Do you understand me? He will never rule."
Then, a few days before the election, Yuda and his colleagues were sent for. They went to their staff offices, where they were told they must cast their votes by postal ballot from the office.
Under a picture of Mugabe, the voting was overseen by war veteran superintendent Shambira, who asked the prison officers to read out their voter identification number.
"Everyone voting knows that Shambira has the power to condemn them as MDC supporters," the film said.
The superintendent told Yuda: "Fold it in the middle like this; and put it in this envelope."
Yuda said: "I took my ballpoint in front of them, in full view of every prison officer. It wasn't a secret. You voted in front of them. You could see them all looking at you voting.
"Then I put my X on Robert Mugabe. This was the most difficult moment of my life because I have never been ZANU-PF."
One man, whose identity was protected, told Yuda: "They are standing right in front of you when you cast your vote. They watch. Shambira definitely sees your vote.
"There's no way of hiding it. I was thinking I could vote when he wasn't looking but he was watching like a hawk.
"Even if he doesn't see you cast your vote he will see it when he folds the ballot paper."