Results for the runoff vote in Mali's presidential elections have been postponed from Wednesday to Thursday for logistical reasons, a senior official said.

The results had been expected to be given on Wednesday at 1730 GMT.

But an aide to the minister for territorial administration Mohamed Ag Erlaf, said the results “will be announced on Thursday” on national television, probably at 0930 GMT, according to other sources.

The delay, he said, will give time for the proper certification of election results to arrive from Tessalit and Menaka in remote northern Mali and from Nampala in the centre.

A member of the commission collating the results nationwide said that these three localities were the last to send in their documents.

The EU, whose observation mission will remain on the ground until the final results are announced, repeated its call on Wednesday for calm during the electoral process.

Sunday's second round of voting saw President Ibrahim Boubacar Keita, 73, face off against former finance minister Soumaila Cisse, 68, in a reprise of the elections in 2013 that saw Keita win by a landslide.

Keita is also the favourite in this year's polls, despite widespread criticism of his handling of a wave of ethnic violence.

Violence, low turnout and accusations of fraud marred the vote. Cisse on Monday said he would reject the results.

On Wednesday, the opposition claimed a technician working for Cisse was tortured while detained by security forces for three days.

Abel Kouassi Konan, an Ivorian employee of Smartmedia which runs the opposition campaign's communications, was arrested on Sunday along with five other French and Malian colleagues, who were released after two hours.

“Abel has been mistreated, tortured and is currently in hospital,” said Cisse's team in a statement Wednesday.

The security forces declined to comment.