The Inkatha Freedom Party's byelection victories had come despite intimidation from the African National Congress, an IFP spokesman said on Thursday.

Zanele kaMagwaza-Msibi said the party had been particularly outraged by the behaviour of the ANC in Mooi River where, she said, police dispersed a crowd of about 300 youths who "wreaked havoc in the ward" on polling day.

"If this is the trend we are going to see in the forthcoming general election campaign, the Independent Electoral Commission will have to pull up its socks to ensure free and fair elections," she said.

She said that in addition to an uncontested win in Nongoma's ward 16, the IFP had also carried three wards in Mandeni, Ulundi and Jozini.

All four were originally IFP seats.

She said candidates and supporters had worked hard on the ground to make these wins possible, "often in the face of voter intimidation by the ruling party".