TOKYO - Many people are feared trapped inside a shopping mall building after an explosion Tuesday in quake-hit Kumamoto Prefecture, with some believed to be injured, according to the Fire and Disaster Management Agency.

The operator, Aeon Mall, had earlier said the explosion occurred after employees and customers had been evacuated from the commercial facility in Kashima following the M7.1 temblor that struck the southwestern Japan prefecture at 4:27 p.m.

The second floor of the building collapsed, according to the agency.

Ceilings and walls at Aeon Mall Kumamoto collapsed, exposing the building's steel framework, while debris was scattered around the complex.

A 44-year-old man who runs a nearby hair salon said he heard a loud noise that sounded like a large vehicle colliding with something.

"I saw a plume of white smoke right after (the explosion)," he said.

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