The body of a Benin tour guide has been found in a national park, the government has said, heightening fears that two French tourists who disappeared with him have been kidnapped.

Autopsy results confirmed that the body found on 4 May "was that of the Benin guide of the two French tourists who are still missing," the interior ministry said in a statement.

France said efforts were under way to find the pair who disappeared in the remote Pendjari National Park.

The unnamed tourists and their local guide went missing on Wednesday in the wildlife reserve around 550km north of Benin's economic capital Cotonou.

The vehicle they were travelling in was found just across the border in Burkina Faso, a security source said, but there was little more for investigators to go on.

The four-wheel drive Toyota car "was found without its occupants" and so "the kidnapping theory is being favoured", the source added.

France 24, citing regional sources, reported that the body of the driver had been found and that he had been shot dead.

A government source said the body had been badly disfigured by the time it was found yesterday.

Pendjari is one of the largest remaining conservation regions for elephants and lions in West Africa, according to a park official.

It is a vast area of 4,800 square kilometres - but just part of a far larger wilderness area spreading into Burkina Faso and Niger to the north.

Benin is considered an island of stability in West Africa, a troubled region where many jihadist groups operate, but Pendjari lies on the porous and remote border with Burkina Faso, hard-hit by militant violence.