Several opposition parties had called for the long-delayed parliamentary election to be postponed due to the Covid-19 pandemic, which has seen 18 people test positive since the country's first case was diagnosed earlier this week.
Mali recorded its first coronavirus death on Saturday, a day before the West African country voted in a long-delayed parliamentary election threatened by both the pandemic and security concerns.
The kidnapping of the leader of the main opposition party earlier in the week has also cast a pall over the vote, with a security source saying he is "likely" in the hands of a militia group.
Several opposition parties on Saturday called for the vote to be postponed due to the Covid-19 pandemic, which has seen 18 people test positive since the country's first case was diagnosed on Wednesday.
Health Minister Michel Sidibe said late Saturday - just hours before polls opened the following day - that a patient who had tested positive had died earlier in the day.
"We have a death today," he said, "because the virus was in his lungs."
Though sub-Saharan Mali has had relatively few cases so far compared to other continents, the impoverished nation of some 19 million people - where large swathes of territory lie outside state control - is just the kind of state experts fear is particularly vulnerable.
Militia recordings claim abduction
In an unprecedented and shocking twist just days before the vote, veteran opposition leader Soumaila Cisse was kidnapped while campaigning in the conflict-ravaged centre of the country.
Cisse, 70, who has come second in three presidential elections, and six members of his team were abducted on Wednesday in an attack in which his bodyguard was killed.
"According to our information, the opposition leader was likely kidnapped by militias from central Mali claiming to be from Amadou Koufa," a security source said.
Fulani preacher Amadou Koufa leads the Katiba Macina militia, a branch of the al-Qaeda-aligned Group in central Mali.
Cisse and his entourage are probably now "far from where they were abducted," the security source said.
A source close to Cisse also said the opposition leader was in the hands of the Koufa's Katiba Macina.
"Not only do we have clear indications from our own sources, but there are also recordings broadcast by the militias," the source said.
Since the abduction, recordings seen by a reporter have circulated on social media in the Fulani and Songhai languages spoken in central and northern Mali of men declaring loyalty to Koufa claiming Cisse's abduction.
Despite the deepening COVID-19 crisis, Cisse's Union for the Republic and Democracy (URD) urged its supporters to turn out in even greater numbers.
"In these difficult times our country is going through, more than ever, the party's activists are resolutely urged to redouble their efforts for a massive participation in the March 29, 2020 elections," the country's main opposition party said Saturday.
But other opposition parties - the National Congress of Democratic Initiative (CNID), Patriotic Movement for Renewal (MRP) and the CMAS movement of influential imam Mahmoud Dicko - called for the vote to be postponed due to the coronavirus emergency.
Three candidates also withdrew from the poll, which will see new MPs elected to the 147-seat National Assembly for the first time since 2013.
The current parliament, which is dominated by President Ibrahim Boubacar Keita's party - Cisse's URD has 18 MPs - was supposed to wrap up in late 2018, but subsequent elections were postponed, mostly over security concerns.
Voters will be supplied with hand-washing kits and masks at Sunday's elections, as well being made to keep separate from each other, the government has said.
After Sunday's first round vote, a second round is scheduled for April 19.
In neighbouring Mauritania, the government announced Saturday that travel between regions would be banned from noon on Sunday.
The vast Sahel country also confirmed two more coronavirus cases, bringing its total to five.