Police have arrested 70 members of Zimbabwe's splintered main opposition party as they campaigned in Harare ahead of a by-election.
A party statement said Arthur Mutambara, who leads a renegade faction of the Movement for Democratic Change (MDC), was arrested along with a large group campaigning door-to-door in Harare's Budiriro township amid what critics say is a broadening crackdown on Mr Mugabe's critics.
MDC officials said at least five other senior members of Mr Mutambara's MDC factio were among those arrested.
The district's parliamentary seat had been held by an MDC legislator who died in office, and political analysts say Mr Mugabe's ZANU-PF is intent on victory in tomorrow's vote to disprove critics who say the party's popularity is plummeting.
Mr Mutambara was elected leader of one faction of MDC earlier this year after a split in the party. MDC founding President Morgan Tsvangirai remains in control of the larger MDC, which Mr Mugabe's government regards as the real threat, political analysts say.
With Zimbabwe's economic crisis seemingly spinning out of control, Mr Mugabe this week turned up the heat on his opponents over fears they were about to launch a wave of anti-government protests which Mr Tsvangirai has threatened to lead.
Rights groups say security forces have banned marches, detained critics and stepped up an intimidation campaign over suspicion opponents could use the commemoration of the government's controversial slum demolition a year ago to launch wider protests.
Yesterday police arrested about 100 people demonstrating for political reforms.
Zimbabwe now has inflation of more than 1,000 per cent, the highest in the world, along with surging unemployment and persistent shortages of food, fuel and foreign exchange. Mr Mugabe (82), blames Zimbabwe's economic problems on sabotage by domestic and Western powers opposed to his nationalistic programme, but mainly his seizures over the last six years of white-owned commercial farms for redistribution to black Zimbabweans.