A group of 17 gunmen entered an animal park in the Central African Republic, threatening "one of the biggest massacres of elephants" in the region, conservationist body WWF said Tuesday.

It said the 17 had on Monday entered the Dzanga-Ndoki national park and were heading for Dzanga Bai, known locally as "elephant village".

The poachers threatened to bring about "one of the biggest massacres of elephants in the region since poachers killed at least 300 elephants for their ivory in Bouba N'Djidda national park in north Cameroon in February 2012, WWF said in a statement sent to AFP in Yaounde.

Dzanga Bai was described as a big clearing where 50 to 200 elephants go each day "to drink mineral salts present in the sands".

"Unless rapid and decisive measures are taken it seems very likely that the poachers will take advantage of the country's chaos and instability to shoot elephants living in this unique site," said Jim Leape, general director of WWF International.

The rebel Seleka coalition toppled the regime of Francois Bozize in March but has yet to establish order in the country whose army is in a shambles.