Beijing, June 14 : At least 19 people were killed and 172 others injured in a tanker blast in China's Zhejiang province, local authorities said on Sunday. The tanker loaded with liquified petroleum gas exploded near the Liangshan village in the city of Wenling on a section of the Shenyang-Haikou Expressway on Saturday evening, Xinhua news agency. A second blast took place when the blown-up truck fell onto a workshop near the expressway. The explosions caused the residential houses and factory workshops to collapse. So far, more than 2,660 rescue personnel, 151 vehicles and over 30 large machinery and equipment have been sent to the accident site, said Zhu Minglian, vice mayor of Wenling, at the press conference. More than 630 medical workers were also mobilized for the treatment of the injured, said Zhu. Local environmental protection authorities carried out real-time monitoring of the air and water around the accident site. No obvious pollution was found so far, said Zhu. Rescue and search efforts are underway. The cause of the accident is under further investigation. /IANS