Villagers from the area most severely affected by Tuesday's toxic gas blowout in southwest China's Chongqing municipality began to return home on Monday.

Five villages of Gaoqiao Township, Kaixian County, within a radius of five kilometers of the gas well, were the most severely affected area of the accident.

"No gas has escaped since the successful sealing of the well on Saturday," said Zeng Shitian, professor and engineer with Sichuan petroleum administration bureau.

The cloudy weather with some rain would help the toxic substances to sink on the earth, said a local meteorological expert.

"According to data analysis of the environment of the site, both the atmosphere and surface water quality are secure enough for villages to return home," said Zhang Shaozhi, director of the Chongqing municipal environmental protection bureau.

From Sunday morning, a 600-strong team conducted a massive disinfection of the area.

Sampling by the epidemic prevention department showed that most drinking water, grain and vegetables were safe enough, said Zhang Chengyong, director of the local disease prevention center on Sunday.

Zhang Hongxin, deputy head of Kaixian County, said vehicles and food had been prepared for evacuees by the county government and everybody had been given an umbrella.

After coming home, villagers should open windows and doors to ventilate their houses, and before going down the cellar, security measures should be taken, environmental protection personnel advised.

They should dispose of water they had preserved before the accident although grain and vegetables were still edible, warned the local government.

Electricity supplies were secured by the local government and all shops should open to guarantee the supply of daily necessities. Medical personnel would accompany victims home to guarantee timely treatment.

Relatives of the dead were advised not to return as bodies were still being identified.