Amid claims of widespread fraud, Zambia's incumbent President Levy Mwanawasa won re-election after vote-counting Monday in Lusaka.

With votes in 135 of 150 constituencies counted, Mwanawasa had 43 percent of the vote to main challenger Michael Sata's 28 percent, the BBC reported. He was narrowly followed by Hakainda Hichilema, who had 27 percent of the vote.

Sata took the defeat bitterly, and alleged fraud when preliminary figures were announced late Sunday.

Once Mwanawasa is declared the winner, I will congratulate him for successfully stealing the vote, he told the BBC.

His supporters began noisy rallies Sunday night and Monday morning, and riot police moved in to dispel them using tear gas and making arrests, the report said.

Under Zambian law, a candidate does not have to attain more than 50 percent of the vote but merely more than any other.