A presidential candidate in the Democratic Republic of Congo has shown Al Jazeera what he says is evidence of election fraud.

Vital Kamerhe says the discovery of many pre-marked ballot papers is proof that Monday's polls have been rigged.

The chairman of the country's electoral commission has denied the allegations, saying an investigation into claims of fraud has already disproven them.

Yvonne Ndege reports from the capital Kinshasa.

Source: Al Jazeera