A soldier secures the are as firemen fight a blaze Wednesday, June 21, 2023 in Paris. Firefighters fought a blaze on Paris' Left Bank that is sent smoke soaring over the domed Pantheon monument and prompted evacuation of buildings in the neighborhood, police said. Local media cited witnesses describing a large explosion preceding the fire, and saying that part of a building collapsed. (AP Photo/Christophe Ena)

PARIS – French rescue workers searched Thursday for a person feared missing after a powerful blast brought down a building on Paris' Left Bank, injuring more than 30 people, four of them critically.

Investigators were working to determine the cause of Wednesday's explosion. A possible gas leak was one of the potential causes under investigation.

The blast near the historic Val de Grace military hospital in Paris' 5th district crumpled the facade of a building that held a private academy of design and arts.

Some of the four critically injured people suffered severe burns, said Health Minister François Braun.

One person who was feared missing has been found. Police said efforts were ongoing to locate another person still feared missing.

With more than 2 million people densely packed within the city limits and historic — sometimes ageing — infrastructure, Paris is no stranger to gas explosions. A January 2019 blast in the 9th district killed four people and left dozens injured.

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