BUNIA, Congo (AP) — The healthcare workers at the epicenter of Congo’s Ebola outbreak are walking off their jobs to protest delays in their payments, threatening efforts to slow the outbreak that officials said continues to spread faster than the response.

In Ituri province, the hardest hit among the three provinces in eastern Congo affected by the outbreak, some of the health professionals and other front-line workers told The Associated Press they’ve not been paid their wages and bonuses since the outbreak was declared on May 15. They also alleged they were working with limited gear, and were being treated unfairly by authorities as well as response teams.