Three Chinese energy firms were told by local authorities in China to halt operations, after massive blasts at a warehouse in Tianjin last week raised public concerns that some facilities storing hazardous materials are too close to homes and schools.
The Tianjin port warehouse, which had stored about 700 tons of the deadly chemical sodium cyanide, was 600 meters (656 yards) from the nearest housing estate.
That was closer than allowed by Chinese laws, state media says.
The government of the coastal city of Hangzhou has told CNOOC Hangzhou Marketing Company to suspend its operations at a facility currently storing at least 3,000 tons of gasoline and diesel.
There are "safety risks," said the Hangzhou government on its website on Wednesday.
No buildings were close to the site when the facility was constructed in 1989, but homes and shops as well as a primary school have sprung around it over the years, it said.
Warehouses of dangerous chemicals occupying an area exceeding 500 square meters should be built at least 1,000 meters from public buildings and transportation facilities, according to regulations published by the National Safety Administration in 2001.
Housing sites have crept closer to industrial parks and ports over the last decade as local governments, keen on the higher taxes and rates, sold off such land to residential developers, said Stuart Ross, head of industrial, China, at property consultant Jones Lang LaSalle.
In southeastern Shenzhen city, the local housing bureau said it had asked two gas firms - Shenzhen Gas and Shenzhen City Shenchanghongyuan Liquefied Petroleum Gas Company - to cease operations by the end of August, adding that it planned to relocate their depots.
While the housing authority said the firms fulfilled government distance guidelines, it decided to shut their operations as it wanted to draw lessons from the Tianjin incident.
The gas storage facilities of the two companies are located 250 meters from a large residential area with a population of 30,000, the official Xinhua news agency said on Wednesday.
Last week, the blasts in the northeastern city of Tianjin damaged 17,000 apartments. The explosions killed 114 people.