Police and public health officials in North Macedonia say at least 10 people have died and many others have been injured by a fire at a makeshift hospital for COVID-19 patients.

The blaze occurred late Wednesday in the western city of Tetovo, where the facility was set up following a recent spike in infections in the region.

Health Ministry officials said injured medical staff and patients along with over evacuees were being transferred to hospitals in the capital Skopje some 45 kilometers (28 miles) to the east.

The cause of the fire was not immediately known, but Prime Minister Zoran Zaev said in a Facebook post that the blaze followed an explosion at the site.

With less than 30% of the country’s population fully vaccinated, North Macedonia has seen a significant spike in infections and deaths since late August.