Death toll in China's China's Gansu Province earthquake has climbed to 75 , local authorities said.As at 6 p.m. Monday, 73 people in Dingxi City and two in its neighboring Longnan City had been confirmed dead in the 6.6-magnitude quake that jolted the border of Dingxi's Minxian County and Zhangxian County at 7:45 a.m., said the Dingxi municipal government. Fourteen people are missing from hard-hit Minxian County, which reported 72 deaths and and 584 people injured. As of 4 p.m. Monday, 411 aftershocks had been recorded in the quake-hit region, with the strongest measuring 5.6 in magnitude, Chang Zhengguo, spokesman for the provincial government, said at a press conference in the provincial capital of Lanzhou.An initial investigation showed that the quake had caused the collapse of more than 1,200 houses and severe damage to 21,000 homes, he added. Two helicopters and about 3,000 armed police, firefighters, local militiamen and local government staff have been sent to the quake-hit region to help with the rescue efforts. Xinhua reporters who arrived at the villages in the seriously-hit Meichuan Township, of Minxian County, said many rural buildings had been reduced to ruins and others had cracks in the walls.A total of 31 people have been confirmed dead in Meichuan, according to rescuers. Zhu Wenqing, a 40-year-old farmer in Majiagou Village in Meichuan, said his house survived the first quake but eventually collapsed following seven or eight aftershocks.Villagers said the victims were mainly the elderly and children, with most failing to escape from collapsing houses.