Chinese authorities have raided the offices of a company at the center of a mudslide disaster that left 76 people missing, with police present at two of its premises on Tuesday and no signs of employees. At least one body has been recovered from the rubble after a giant deluge of mud and construction waste from an overfull dump site buried 33 buildings at an industrial park in the southern boomtown of Shenzhen on Sunday. It was the second major man-made disaster in China in four months — in August, at least 160 people were killed in massive chemical blasts in the northern port city of Tianjin. With growing worries about China's industrial safety standards, Premier Li Keqiang ordered an investigation within hours into the mudslide in Shenzhen, a town that has boomed with China's breakneck economic growth. The dump site is being managed by a company called Shenzhen Yixianglong Investment Development. At its registered office, an apartment in a Shenzhen residential suburb, a Reuters reporter saw police taking pictures inside the room but was quickly warned away. Officers were also in the hallway and an adjacent apartment where some of them were standing over a woman crouching over the floor with her head in her hands. It was not clear if the woman was linked to the company in any way or had been arrested. Police told the reporter to leave the building, and that the company had already moved. "This does not concern you," one of the officers said. A separate office on the ground floor of the building bearing the company's name was empty and locked, with wilted plants inside. At a second site for the company, an office building in an industrial estate, police officers in the lobby prevented a Reuters reporter from going upstairs. There were no signs of any employees. Calls to the company went unanswered. Shenzhen police did not immediately respond to a request for comment, nor did the Shenzhen government. The government had warned the site, which was supposed to be temporary, was unsafe. In September, local district authorities said on an official website the dump was not supposed to take any more waste and that guards were meant to have been posted to prevent illegal dumping of mud. Residents have told Reuters that waste continued to be dumped at the site. "It was definitely dangerous," said Jiang Xuemin, 44, who lived and worked inside the industrial park. "Every day there were trucks moving mud, every day there were hundreds of them, truck after truck after truck," she said. "They were always there, blocking the roads, so many of them." The local district office did not answer telephone calls. At the 380,000-sq m (94-acre) disaster site, workers were searching the rubble, using sensors, drones and earth excavators to reach possible survivors trapped under mud up to 10 meters (33 feet) deep. Overnight, the area was lit up with floodlights to allow uninterrupted rescue operations. A report carried on the China defense ministry's website said police and military forces were in a "race against time." It said rescuers had freed some people trapped in damaged buildings. Rescue dogs roamed over the site looking for survivors, while curious bystanders stood at the fringes. The smell of freshly churned earth mixed with faecal matter drifted through the air. According to state television, 76 people were still missing and believed buried in the rubble.