JUBA, South Sudan (AP) — The death toll from clashes between displaced people inside a U.N. site in South Sudan has risen to more than 20, with more than 50 others wounded, the medical charity MSF said Friday.

The statement by the organization, which is also known as Doctors Without Borders, said that two of its staff were among those hurt. Some of the injured were being airlifted to the capital, Juba.

“While the situation was relatively calm this morning, many women and children who fled the camp are yet to return in fear of escalation,” said Luz Linares, MSF’s head of mission in the country.

Thursday’s clashes in the Malakal camp occurred between members of the Shilluk and Nuer ethnic groups, a local representative of the displaced people told The Associated Press. The U.N. office in South Sudan said the fighting began with a stabbing, and that its mission had reinforced the military and police presence in the area in “close collaboration” with South Sudan’s military and authorities.

Deadly violence between ethnic groups and communities still troubles South Sudan years after a 2018 peace deal to end a five-year civil war. During the conflict, thousands of people took shelter inside U.N. protection sites.

More than 41,000 people are staying in the Malakal site, which is also a designated camp for people fleeing the violence in neighboring Sudan, MSF said.