The 7.1-magnitude quake struck the southwestern region of Kumamoto prefecture on Kyushu island on Tuesday afternoon, causing widespread damage, sparking fires and leaving tens of thousands of homes without power."Thirteen people have died," Takaichi said a day after the tremor that registered at the highest level on Japan's shindo scale of seismic shaking."Extensive damage has been confirmed, including casualties, collapsed buildings, fires and damage to roads," Takaichi told reporters, adding that officials were confirming whether all the fatalities were caused by the tremor.The dead on the island of Kyushu included two women in the mall and three more elsewhere, the Fire and Disaster Management Agency told AFP earlier. Seven people were severely injured.The mall in the town of Kashima was apparently gutted by a gas explosion, a government source told the Kyodo news agency, collapsing ceilings and walls."The explosion occurred after the customers and staff had evacuated," a spokesman for the mall's operator Aeon told AFP.Eight people were rescued from the mall, five of whom had injuries, a local official told AFP.Initial reports said that as many as 20 to 30 people were trapped inside but broadcaster NHK cited police early Wednesday as saying that the number was "lower than that".