The Kenyan electoral commission is investigating politicians involved in widespread buying of voting cards ahead of general elections due in December.
Commissioner Jack Tumwa said opposition and government leaders are participating in the scheme that will disenfranchise many voters.
Opposition leaders have intercepted hundreds of voting cards allegedly purchased from their strongholds.
The Electoral Commission says more than 14m voters have registered to vote.
President Mwai Kibaki, is seeking a second term in office but faces a stiff challenge from Orange Democratic Movement (ODM) party leader Raila Odinga.
Commissioner Tumwa confirmed that several cards intercepted were genuine and appealed to Kenyan voters to resist the temptation of selling the cards.
“It has cost the government a lot of money and for one to decide to sell his voting card and deny himself a right to vote is very unfortunate,” Commissioner Tumwa said.
The commission, meanwhile, plans to launch a massive awareness campaign on the importance of participating in an election later this month.
A recent survey by the International Republican Institute shows that many sitting MPs are unpopular with the voters and may be voted out at the elections.
And the latest opinion polls place opposition leader Raila Odinga well ahead of President Kibaki.
Political analysts argue the surveys may have caused a panic, forcing politicians to engage in vote buying in an effort to secure their strongholds.