Late at night on April 14 2016 7.5 miles (12 km) below Mt. Kinpu Northwest of Kumamoto City plates slipped instigating a magnitude 6.4 earthquake which caused major damage in the area east of Kumamoto and inspired more than 140 aftershocks over the following two days. This was overshadowed by a main shock of 7.1 at 1:25 AM on the 16th, the most powerful quake recorded in Kyushu in modern times, and a trembler which brought down many already damaged buildings and weekened hillsides. At least 35 people were killed and more than 2,000 others were injured. By April 18, the number of people seeking shelter had surpassed 180,000. IDRO members arrived in Mashiki, one of the worst hit areas, in the predawn hours of April 19th, setting up base alongside an advance team from Nippon Zaidan.