Dozens of people were wounded Monday in ethnic clashes in the west African state of Guinea, officials told AFP, after petrol station guards killed a youth from a rival tribe.

A police source said the violence broke out in the southern forest region when the guards from the Guerze tribe accused the youth, an ethnic Konianke, of stealing before torturing and beating him.

The victim's family told their fellow Konianke tribespeople who "rose up against these medieval practices" in the town of Koule, the source said.

The violence spread to the nearby provincial capital N'Zerekore, 570 kilometres (350 miles) southeast of Conakry, leaving dozens injured and several homes destroyed.

Security forces deployed to break up the fighting had been unable to restore calm in N'Zerekore by the afternoon, witnesses told AFP, while the police source said there were "dozens wounded by machetes".

"The two communities are now fighting with machetes, axes, sticks and stones. I cannot say the exact number of casualties in the districts or even the number in hospital. The situation is extremely serious," he added.

"Since the clashes broke out in Koule overnight and moved to N'Zerekore, we have registered one death and at least 50 injured, 20 in Koule and 30 in N'Zerekore," a hospital source told AFP.

Communal violence is common in the region, near the border with Liberia, where clashes between the two tribes regularly break out over religious and other grievances. The indigenous Guerze are mostly Christian or animist, while the Koniankes – seen as newcomers – are Muslims considered to be close to Liberia's Mandingo ethnic community.

In Liberia's civil war, which ended in 2003, rebels fighting the forces of then president Charles Taylor drew much of their support from the Mandingo community.

The Guerze, known as Kpelle in Liberia, were generally considered to be supporters of forces loyal to Taylor, who was jailed last year for "aiding and abetting" war crimes in neighbouring Sierra Leone.