Their release came just days after Malian authorities freed nearly 200 jihadist prisoners, fueling speculation that an exchange was imminent.

A prominent Malian politician and three European hostages freed by Al Qaida-linked Islamic extremists arrived in Mali’s capital late Thursday where they were greeted by family members and supporters.

The politician, Soumaila Cisse, a three-time presidential candidate, was greeted by his son. The French humanitarian Sophie Petronin, who had been abducted four years ago while helping orphans in northern Mali, arrived in a flowing white traditional dress.

While their relatives had been notified of their release on Tuesday, news that two Italian hostages also had been freed came only late Thursday in a government statement once the flight had left northern Mali.

“Father Pierluigi Maccalli and Nicola Chiacchio, kidnapped in Africa between 2018 and 2019, are free and are returning to Italy!” Prime Minister Giuseppe Conte of Italy tweeted.

Father Maccalli, a Roman Catholic priest from the African Missionary Society, was kidnapped from his parish in Niamey, Niger, according to the Avvenire newspaper of the Italian bishops conference.

Mr. Chiacchio was taken from central Mali in 2019, according to Menastream, an independent consultancy specializing in the Sahel and North Africa. The two were believed to be held by the same extremists after a video was released of them together in April.

Mr. Cisse was re-elected to his parliament seat while in captivity and has now emerged as the front-runner for the 2022 election. Extremists had ambushed his vehicle in March while he and his entourage were campaigning in northern Mali.

Negotiations for Mr. Cisse’s release had appeared to stall after an Aug. 18 military coup overthrew the democratically elected president, Ibrahim Boubacar Keita, who defeated Mr. Cisse in both the 2013 and 2018 elections.

The military junta has handed over power to a transitional government now tasked with organizing elections, though the junta’s leader still serves as vice president.

The hostages’ release came just days after Malian authorities freed nearly 200 jihadist prisoners over the weekend, which had fueled speculation that a prisoner exchange was imminent.

There was no immediate information on whether a ransom was paid. Extremist groups in the Sahel have long funded their organizations through kidnappings.

The Al Qaida-linked group, known as JNIM, and its associates are believed to be still holding the Australian doctor Ken Elliott and the Colombian nun Gloria Cecilia Narváez Argoti. In addition, Christo Bothma of South Africa, Beatrice Stockly of Switzerland and Julian Ghergut of Romania are also still being held.