JOHANNESBURG — Opposition leaders say the Zimbabwean government is printing millions more ballot papers than there are registered electors — raising fears of a huge vote-rigging operation ahead of next weekend’s election.

The registered electorate for the presidential and parliamentary polls is about 5.9 million.

But the Movement for Democratic Change says it has obtained leaked documents showing nine million papers have been ordered. Robert Mugabe, who is seeking a sixth term in office, is in a three-way fight with MDC leader Morgan Tsvangirai and a former finance minister from the ruling Zanu-PF party, Simba Makoni.

If used in Mr. Mugabe’s favor, the extra ballot papers would be enough to ensure that he passes the 51% of the vote required to be declared the outright victor.

At a rally in Harare yesterday, Mr. Tsvangirai told tens of thousands of supporters: “The polling stations will open late and there will be no power, no lights. They will have trouble with the toilets and they will be in a muddle with the ballots and the voters’ roll.”