TOKYO, July 5 (Reuters) - Rescuers in Japan searched on Monday for 80 people believed to be missing two days after landslides tore through the seaside city of Atami, destroying houses and burying roads under mud and rock. The official death toll from the landslides that hit early on Saturday is four, according to Atami city spokesperson Hiroki Onuma, while the number of missing had come down from 113 earlier. Two people were found alive and unharmed on Monday, the NHK public broadcaster reported. "My mother is still missing," one man told NHK television. "I never imagined something like this could happen." Atami, with a population of 36,000, is 90 km (60 miles) southwest of Tokyo, set on a steep slope leading down to a bay. It is famous for a hot springs resort. The landslides are a reminder of the natural disasters - including earthquakes, volcanic eruptions and tsunami - that haunt Japan, where the capital Tokyo is to host the summer Olympics beginning this month. By Monday, the number of rescuers at the disaster site had risen to 1,500, officials said. Prime Minister Yoshihide Suga said police, firefighters and members of the military were doing all they could to help with the search. "We want to rescue as many victims ... buried in the rubble as soon as possible," Suga told reporters. Members of Japanese Self-Defence Forces conduct rescue and search operartion at a mudslide site caused by heavy rain at Izusan district in Atami, west of Tokyo, Japan July 5, 2021, in this photo taken by Kyodo. Kyodo/via REUTERS Members of Japanese Self-Defence Forces conduct rescue and search operartion at a mudslide site caused by heavy rain at Izusan district in Atami, west of Tokyo, Japan July 5, 2021, in this photo taken by Kyodo. Kyodo/via REUTERS A 75-year-old man had a lucky escape when the house across from his was swept away. The couple living there are missing. "This is hell," the man said from an emergency shelter. The landslides were triggered by torrential downpours - with some areas receiving more rain in 24 hours than they would usually get for the whole of July. About 130 buildings were affected in Atami. Chief Cabinet Secretary Katsunobu Kato called for vigilance, with the ground so saturated and weakened that even light rain could prove dangerous. Onuma said the rain had stopped in Atami but more was forecast. "The situation is unpredictable," he said. The disaster boosted the stocks of some engineering firms on Monday. Raito Kogyo Co Ltd (1926.T), an expert in slope and foundation improvement, rose 1.3%, while CE Management Integrated Laboratory Co Ltd (6171.T), which offers geological survey and disaster prevention systems, gained 3.1%.