Many people have died in a fire in a building in Brussels

Several people died in a fire at a building under construction in Brussels on Tuesday, local authorities said.

The cause of the fire at the Oxy Tower in the city center is unclear. Authorities say at least six people are missing.

As it quickly disappeared, firefighters entered the building and discovered it had spread to the hoist shafts, where two hoists were stuck.

They opened one and found “several victims – we don’t yet know exactly how many,” said Brech Spybrook, a spokeswoman for the Brussels labor prosecutor’s office.

“It could be the six people who are missing, but there could be more in the other elevator or somewhere else,” he added.

Brussels Mayor Philippe Clouse praised the emergency services for their “exceptional work” in “particularly difficult circumstances”.

Belgium’s King Philippe is expected later as Prime Minister Bart de Wever arrives at the scene, Belgian outlet RTBF said.

According to local media, two people have already been taken to the hospital with severe burns, and a firefighter was treated at the scene after being exposed to high temperatures.

The Oxy Tower is still under construction and will eventually house apartments, a hotel, restaurants and bars.

Located 500m (0.3 miles) from the Grand Place, Brussels’ central Baroque square.