The soldiers were taken across the border to an area near the Gambian village of Bajagar and delivered to officials from the Gambian government and the West African regional bloc ECOWAS, according to AFP correspondents present.

The freed hostages appeared in good health and left the area in Red Cross jeeps. The charity stated that it had visited the soldiers in captivity and provided medical care.

The release comes after a clash between fighters from the Movement of Democratic Forces of Casamance (MFDC) and the Senegalese army on January 24.

Four Senegalese soldiers were killed, while seven were captured alive.

Senegal's military said the incident occurred during an operation to combat illegal logging on the border with The Gambia.

But MFDC leader Salif Sadio said last week that Senegalese soldiers stationed in The Gambia had crossed the border and attacked his bases in Casamance.

The captured soldiers were part of the peacekeeping mission from the West African bloc ECOWAS in The Gambia, which is known as ECOMIG.

The MFDC is behind a low-intensity separatist conflict in Senegal's southern region of Casamance dating to 1982 that has claimed several thousand lives.

Casamance was a Portuguese possession for several hundred years until it was ceded to colonial France in 1888. It became part of Senegal after the country gained independence in 1960.

The region, which has a distinct culture and language, is separated geographically from the rest of Senegal by the Gambia River, around which lies the tiny state of The Gambia.

- Nothing in return -

The MFCD is split into several factions, with one headed by Sadio.

One of the ECOWAS representatives present the handover, Claude Kondor, said that the group had demanded nothing in return for freeing the soldiers.

However, MFDC official Pape Sane warned at the handover ceremony that the rebel group would not tolerate any intrusion by Senegalese forces on what it considers its land by ECOMIG forces.

"We have no problem with The Gambia," Sane said. "But foreigners hosted on Gambian soil must stay in The Gambia."

Comprising mainly Senegalese soldiers, ECOMIG was deployed to The Gambia in January 2017 when former dictator Yahya Jammeh refused to cede power after losing a presidential election.

Its mission has continued at President Adama Barrow's request despite Jammeh's departure into exile.

Casamance rebels, f are accused of trafficking timber and cannabis, have traditionally sought refuge in The Gambia or Guinea-Bissau, which also borders Senegal.

The conflict had been mostly dormant until Senegal's army launched a major new offensive last year designed to drive out the rebels.

Senegalese President Macky Sall has made achieving "definitive peace" in Casamance a priority of his second term.