The West African intervention force, ECOMOG, says it's been involved in further fighting with rebel forces in northern Sierra Leone.

A spokesman for ECOMOG said fierce battles were continuing between the West African troops, backed by pro-government militias, and rebel soldiers -- around the town of Masiaka, sixty kilometres east of Freetown.

The fighting is reported to have begun on Sunday after rebels attacked a checkpoint manned by pro-government militias, who have been deployed to counter an upsurge in rebel attacks.

Hundreds of civilians are now reported to be fleeing the area.