Soldiers and emergency workers continued to comb through a damaged shopping mall and collapsed houses in southwestern Japan on Wednesday, searching for survivors after a powerful earthquake killed at least 18 people.

The magnitude 7.1 earthquake struck the Kumamoto area on the southern main island of Kyushu on Tuesday, also injuring at least 62 people, six of them seriously, according to the prefectural government. The death toll has been steadily rising.

Rescuers faced challenging conditions due to sweltering weather. The number of people still missing remained unclear.

Significant damage was reported at the Aeon Mall shopping center in Kashima city, which was crowded when the earthquake occurred. The company stated that approximately 3,000 customers were evacuated before a gas explosion at the mall, where some employees were still present. The mall's second floor collapsed, trapping individuals. Witnesses reported that the explosion added to the impact of the quake. Aeon President Akio Yoshida confirmed four deaths at the mall site, with three people still missing. He expressed the company's seriousness regarding the explosion and loss of life.

Japanese media showed footage of the mall with a caved-in ceiling and debris scattered on the ground as rescue workers searched the site.

In nearby Yatsushino, a chimney collapse at a Nippon Paper Industries factory resulted in five fatalities. Seven people were rescued from the debris at the factory, and four individuals were believed to still be trapped there, according to the Kumamoto prefectural government disaster team.

The first reported death of a foreign national was a Vietnamese technical intern killed by a falling crane at a factory where he worked. He had arrived in Japan in January. Seven other Vietnamese technical interns at the factory evacuated safely. A Vietnamese woman married to one of the factory workers was injured when a wall collapsed and was receiving hospital treatment.

Nearly 34,900 homes were without electricity and about 15,000 homes were without running water, according to Kumamoto officials. More than 8,800 people evacuated their homes and are staying in over 400 shelters.

Aerial police footage revealed that some residential homes were completely flattened, with some structures collapsing into a nearby river.

Japan's Self Defense Forces joined the rescue efforts, alongside hundreds of professionals, including firefighters from Taiwan. Prime Minister Sanae Takaichi stated that the government was preparing to deliver essential supplies to affected areas and expressed condolences to victims' families.

Bullet train services remained suspended following the earthquake. While Aso Kumamoto Airport resumed operations on Wednesday, some airlines canceled flights as a precaution.

Kumamoto experienced a deadly earthquake in 2016 that claimed at least 50 lives. Japan is situated in a highly seismically active region.