Time was running out to find survivors on Thursday as rescuers continued to work in the Kumamoto area on Japan 's southern main island of Kyushu, where the magnitude 7.1 earthquake hit Tuesday. The quake left at least 63 people injured, five of them seriously, the Kumamoto prefectural government said. Chief Cabinet Secretary Minoru Kihara, speaking to reporters Thursday, gave a higher number for the death toll at 28. The Ministry of Environment sent out a heat stroke alert for the Kumamoto area, with temperatures expected to reach as high as 33C on Thursday. Family members of those still missing could be seen wandering helplessly near the wrecked mall, waiting for word, despite the sweltering weather.