France has suspended two soldiers accused of sexually abusing children as young as five during their deployment in Burkina Faso for anti-Islamist operations in West Africa, the second child rape scandal to hit the French army in recent months.

Prosecutors in Paris told Le Monde newspaper they have opened an investigation into the allegations after the Defence Ministry confirmed it took temporarily disciplinary action against the pair, who have not been named.

"Two French soldiers on mission in Burkina Faso are suspected of having engaged in acts of a sexual nature with two children," the ministry told AFP.

One of the two alleged victims is the 5-year-old daughter of friends of the servicemen. Her father learned about the abuse after discovering footage showing one of the soldiers touching the girl on a video camera the suspects left behind, Burkina Faso authorities told the news agency.

The alleged child abusers were part of a 220-strong contingent France deployed to Burkina Faso as part of a wide counter-terrorism operation codenamed Barkhane, launched last year in the wake of the 2013 military intervention in Mali.

About 2,800 other troops are stationed in countries of the Sahel region, including Chad and Niger, as part of the same effort.

The allegations of paedophilia carry a heavy blow to the reputation of the French army in Africa, which was already tarnished by a similar case in April.

Some 14 French soldiers with peacekeeping forces in the Central African Republic have been accused of child abuse after a number of boys claimed they were forced into sexual intercourse, often in exchange of food or money, at a centre for displaced people in the capital, Bangui.