Image copyright AFP Image caption Frenchmen Laurent Lassimouillas (L) and Patrick Picque are among four captives freed

Four foreign hostages have been freed by French forces in the West African country of Burkina Faso, France says.

Commanders launched the operation to rescue two French tourists snatched in neighbouring Benin earlier this month, before they could be handed over to militants in Mali.

During the raid special forces found the kidnappers were also holding a US woman and a South Korean woman.

Two French soldiers and four kidnappers were killed. Two kidnappers escaped.

What do we know about the raid?

It took place in the north of Burkina Faso as the kidnappers stopped on their journey towards Mali, the head of the French military said.

Commanders decided to act because the kidnappers were close to the Malian border and were believed to be planning to hand the hostages over to the Mali-based militant group Katiba Macina.

"Once the hostages were in their hands it would have been impossible to rescue them," General François Lecointre told reporters.

He said that a first operation, conducted on Tuesday with US support, had allowed the French to track the kidnappers.

During the raid itself, special forces covered 200m (219yds) of open ground and got to within 10m of the shelter where the hostages were being held before being spotted by a guard.

The two French soldiers who died were killed at close quarters as they entered one of the kidnappers' four shelters, the general said.

Troops did not expect to find the US and South Korean hostages because there had been no information that the kidnappers were holding anyone else, French Armed Forces Minister Florence Parly said.

Ms Parly said the kidnappers' identity was not yet known but there were two main militant groups operating near where the French tourists were taken, one linked to al-Qaeda and the other to the Islamic State group.

The two soldiers killed during the rescue were named as Cédric de Pierrepont and Alain Bertoncello.

Image copyright AFP Image caption Cedric de Pierrepont and Alain Bertoncello were killed in the raid

Ms Parly thanked the militaries of Benin and Burkina Faso for their help in the operation.

Who are the hostages?

Frenchmen Patrick Picque and Laurent Lassimouillas, both music teachers, disappeared in the remote Pendjari National Park in northern Benin where they had been on safari.

The disfigured body of their guide was found shortly after they disappeared on 1 May, along with their abandoned vehicle.

The park is on the border with Burkina Faso where Islamist militants have been increasingly active in recent months.

The other two liberated hostages had apparently already been in the kidnappers' hands for 28 days, Gen Lecointre said.

South Korean media quoted a government official as saying the authorities had had no report of a missing citizen and they were trying to establish the rescued woman's citizenship.

Meanwhile the US has expressed its gratitude to France for the American woman's release, AFP quoted an official as saying. France said it was likely that she would be "repatriated independently" from the other three.

President Emmanuel Macron is to receive the two French hostages and the South Korean at Villacoublay outside Paris on Saturday, French news outlet BFMTV reports.

What reaction has there been?

A statement from the French said Mr Macron "bows with emotion and solemnity before the sacrifice of our two soldiers who gave their lives to save those of our citizens".

Ms Parly said "terrorists who attack France and French citizens should know that we will spare no effort to track them down and fight them".

France has 4,500 troops based in the Sahel region on the southern edge of the Sahara Desert as part of its Operation Barkhane - an ongoing coalition effort in Africa's Sahel region to fight jihadist insurgents.

A total of 24 French soldiers have died in the region since 2013, when France intervened to drive back jihadist groups who had taken control of northern Mali.