KUMAMOTO — Japanese emergency workers battled today to rescue any remaining survivors from a devastated shopping mall, as the death toll from a major earthquake hit 30 and thousands sweltered in punishing heat.

Prime Minister Sanae Takaichi issued the new tally as Kumamoto officials said they have now extracted four bodies from the mass of rubble, steel and wires of the Aeon shopping mall after a suspected gas blast following Tuesday’s quake.

At the mall, “we have pulled out 10 people. Of them, four were confirmed dead. Another is without vital signs. Another five have suffered severe and minor injuries”, an official from disaster management office in the southwestern region told AFP.

Tuesday’s 7.1-magnitude tremor caused widespread damage, flattening homes, damaging bridges, triggering fires and leaving tens of thousands of residents without power and water in temperatures forecast to hit 38°C this weekend.

Hundreds of elderly people — Japan has the world’s second-oldest population — slumbered on thin mats on the hard lobby floor at a community centre in Uki city as they sought relief from the punishing heat.

“Thank God for these shelters,” said one woman, who declined to give her name, as people slept between chairs and tables or gathered around a television to watch the news.

She had tried to stay home, or rest in her car, “but it’s too hot and there are too many mosquitoes”.

“In this heat, if you don’t have electricity and air conditioning, it’s very tough,” chimed in father-of-four supermarket employee Hiroyuki Matsushima, 53.