When initial results in the race for the Zambian presidency were revealed this week, the sudden fall of the Patriotic Front's nominee caused a riot.

The BBC reported that when state officials named current President Levy Mwanawasa as the front-runner with two-thirds of electoral results in Thursday, effectively overtaking the Patriotic Front's Michael Sata, who led in earlier tallies, police in Zambia's capital Lusaka were forced to use tear gas on Sata supporters gathered to support their candidate.

The riot occurred at main vote counting center in Lusaka and resulted in a series of arrests before it was dispersed, but the controversy surrounding the national election appears far from over, the BBC said.

It is expected that Sata, who now sits in third place behind Hakainda Hichilema of the United Democratic Alliance, will contest the electoral results and demand an investigation into thousands of missing ballots.

The BBC said that while international observers have praised the African nation for its electoral process, its electoral commission has recently been criticized for delays in electoral announcements.