The Ministry of Emergency Management on Friday ordered the Shanghai municipal government to closely investigate a fire that claimed eight lives in the city's Jinshan district.

The fire broke out on Thursday afternoon in a factory of Sheng-Rui Electronic Technology (Shanghai)Co.

According to Xinhua News Agency, the factory produced electronic accessories.

A total of 123 fire engines, eight firefighting robots and 976 firefighters went to the site to extinguish the fire. After 17 hours, the fire was put out at 6:20 am on Friday, according to a release from the city's information office.

Because of the complex interior structure and heavy smoke from burning production equipment, four workers were trapped inside the facility.

Two firefighters and two technicians who went in to rescue them also lost contact before their bodies were discovered on Friday along with those of the other previously trapped four.

The district information office said that assessments of the air and water in the surrounding areas showed no abnormalities and the water used to fight the fire has been collected and stored for treatment.

Sheng-Rui Electronic Technology had been ordered to rectify problems immediately after a safety inspection on Feb 25 by the fire and rescue department of Jinshan district.

The company is owned by Rikai Computer Accessory Co, which is a subsidiary of Apple Inc supplier Luxshare Precision Industry Co.

According to current regulations, a safety incident with fewer than 10 casualties is classed as Grade 3 out of a four-grade system with Grade 1 being the highest.

While a Grade 3 incident is usually handled by prefecture-level government, or as in this case, by the Jinshan district government, the Ministry of Emergency Management has ordered Shanghai municipal government to seriously look into the cause of the fire to prevent future incidents.