Lusaka - Zambia's electoral authorities on Wednesday denied opposition accusations that it was planning to rig next week's elections in favour of acting President Rupiah Banda.

Electoral Commission of Zambia (ECZ) chairperson Florence Mumba said she will investigate all complaints filed concerning the October 30 polls but denied any malfeasance on her part.

"I wish to reiterate the ECZ's commitment to the service of the people of Zambia through the delivery of a credible and acceptable presidential elections," Mumba said in a statement.

Zambians vote next week to replace president Levy Mwanawasa, who died in August after suffering a stroke.

The opposition have accused some senior ECZ staff of engaging in electoral fraud, including ballot tampering, to favour the ruling party.

Four candidates are taking part in the vote, but the leading contenders are Banda and main opposition leader Michael Sata.

Hakainde Hichilema of the United Party for National Development and Godfrey Miyanda of the Heritage Party are also running.