Congolese main challenger in the country’s just ended elections has reportedly died of Covid-19 a day after elections were held in the country.

Guy-Brice Parfait Kolelas died as he was being transferred to France for treatment, his campaign director said Monday on Monday.

Kolelas “died in the medical aircraft which came to get him from the country’s capital, Brazzaville on Sunday afternoon,” Christian Cyr Rodrigue Mayanda told AFP.

The sixty-year-old tested positive for Covid-19 on Friday afternoon, and was unable to host his last campaign meeting in Brazzaville.

Sunday’s presidential election was boycotted by the main opposition and took place under an internet blackout, with critics voicing concerns over the transparency of polls seen as tilted towards veteran leader Denis Sassou Nguesso.

Kolelas was seen as the main rival to Sassou Nguesso, who has lead the central African country for a total of 36 years since 1979.

On Saturday, he posted a video from his sickbed, declaring he was “battling against death.”

“Rise up as one person… I’m fighting on my deathbed, you too fight for your change,” he urged his supporters, saying the election was “about the future of your children”.

Mayanda called on Kolelas’ supporters to rally at 1100 am local time (1000 GMT).

“We’ll continue to count the ballots. He was ahead in a number of areas,” he said.

Provisional election results are not expected for days, but Sassou Nguesso is widely expected to win.