Protesters have taken to the streets of Haiti’s capital to demand the suspension of a runoff presidential vote over alleged irregularities. The demonstrations in Port-au-Prince on Monday came as attackers in rural areas burned several electoral offices. Some of the thousand-strong group of protesters burned vehicles, threw rocks and attacked a petrol station in the downtown area of the capital.

Haiti is due to hold a runoff vote backed by international donors on Sunday, but tensions have risen since the opposition candidate Jude Celestin said last week he would withdraw. Celestin accuses electoral authorities of favouring the ruling party. “We are moving toward a selection, not an election,” Celestin told the Associated Press on Saturday.

The Swiss-trained engineer came second in an October first-round vote in the poor Caribbean nation, beaten by banana-exporter Jovenel Moise, the ruling party candidate. Elections and transfers of power in Haiti have long been plagued by instability, and international observers said October’s vote was relatively smooth. However, several of the 54 candidates said the government had twisted the results.