(CNN) An explosion near a pub in the northern Japanese city of Sapporo on Sunday night injured at least 42 people, including one critically, said Hokkaido Police public relations officer Ryohei Kashihara.

A subsequent fire caused one building to collapse. Residents reported smelling gas after the explosion and seeing broken windows in the area, public service broadcaster NHK reported.

The cause of the explosion, which occurred around 8:30 p.m. local time, is unknown, and emergency services continue to investigate.

Video shows the blast's destructive aftermath. Firefighters sprayed water onto the building's remnants, and debris was strewn across the nearby street.

The explosion also shattered windows across the street, sending broken glass onto the sidewalk, a Twitter user posted.

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