Mercury has been removed from a total area of 30,000 square meters at the warehouse in Thanh Xuan District.

To prevent the mercury from spreading and leaking into the environment, 120,000 liters of chemicals were used during the 23 days of the cleanup, Senior Lieutenant Colonel Dau Xuan Hoai, deputy head of the Military Institute of Environmental Chemistry, said.

The division said the environment at the site, which is close to schools and residents' homes, had reached safe levels by 4 p.m. on Saturday.

"We have asked the city environment department to get an independent inspection unit to do tests to make sure," Hoai said.

The Urban Environment Company Urenco 10, which helped with the cleanup, collected 1,200 tons of ash, 1,300 tons of construction debris and 11 tons of burned light bulbs.

The waste has been taken to the Nam Son landfill, the biggest one in the capital. It's not clear how it will be treated there.

A five-hour blaze that started at 6 p.m. on August 28 destroyed a third of Rang Dong warehouse’s stocks.

An estimated 15.2-27.2 kilograms of mercury were released into the environment, according to the Vietnam Environment Administration.

Over 130 army and civilian personnel have been cleaning up the site since September 12, with the former in charge of mopping up the mercury and Urenco 10 clearing the rest.

The Ministry of Public Security said last month the fire was caused by a short-circuited light bulb.

Its Institute of Forensic Sciences found that a problem in the electric circuit of an LED light bulb on the second floor, where several products and materials were stored, caused the fire.

People living nearby have moved out of their homes due to health concerns though authorities have tried to allay their fears.

Health officials said no mercury poisoning has been detected in 1,000 people who had health checks.

Minister of Natural Resources and Environment Tran Hong Ha said on September 12 that areas around the warehouse are safe.

Rang Dong, a leading manufacturer of lighting products and equipment, has estimated its loss at VND150 billion ($6.4 million).