Brussels — A firefighter died and three other emergency personnel were severely injured in two explosions on Friday as they responded to a gas leak at a building in central Brussels, news agency Belga reported.

The three injured are said to be a firefighter and two employees of the Brussels public gas infrastructure company Sibelga.

The gas leak was caused when a construction worker accidentally drilled into a low-pressure pipe.

The two explosions did not occur at the damaged gas pipe, but inside the building itself, said Serena Galeone, the spokeswoman of public gas infrastructure company Sibelga.

Around 100 people were evacuated earlier on Friday from the building close to Brussels' central train station, which also houses a European Union agency.

Two tram lines were temporarily interrupted as police had set up a security cordon.