Three Chinese nationals kidnapped in Mali in July escaped their captors at the weekend and were rescued by security forces on Monday, the Sahel state's army said.

On July 17, armed men attacked a construction site in the southwest of the conflict-ridden country, making off with pick-up trucks and five hostages: three Chinese men and two Mauritanian nationals.

The Mauritanians were freed 10 days later.

But the remaining Chinese captives managed to stage a successful escape on Sunday, according to a Malian army statement.

Ground and air forces then located the men the following day, in a joint operation whose success was aided by "anonymous people of good will".

The escaped hostages are in reasonable health, according to the army, which hailed their "bravery and pugnacity".

The operation comes only weeks after Colombian nun Sister Gloria Cecilia Narvaez, who was kidnapped by jihadists in 2017, was freed in Mali on October 9.

Abductions have been frequent in the country's brutal jihadist conflict, which first broke out in 2012 but has since spread to neighbouring Burkina Faso and Niger.

French journalist Olivier Dubois was abducted in northern Mali on April 8. Dubois said in a hostage video that the Group to Support Islam and Muslims (GSIM), the largest jihadist alliance in the Sahel, had kidnapped him.

Thousands of people have also been killed and hundreds of thousands have fled their homes in Mali's conflict, while the economic impact on one of the world's poorest countries has been devastating.