An aid group says thousands of people have fled the town of Pinga in eastern Congo following renewed fighting between local armed groups.

Jan Peter Stellema, the head of operations in Goma for Doctors Without Borders, said Friday that residents of the area have faced constant turmoil since 2012.

Most of Pinga's population now has fled into the forest, while others have taken refuge in the hospital run by the aid group.

Doctors Without Borders, also known by its French acronym MSF, said 11 of its local staff members were missing.

The town, which is located along the border between the Masisi and Walikale territories, has been the scene of brutal attacks by local militias.

Aid workers say the town has changed hands eight times in the last year.