Eleven workers have died in an explosion at a fireworks factory in southern China.

Seventeen others were injured in the blast, which happened in the city of Cenxi in the Guangxi region, 1,200 miles southwest of Beijing. The explosion reduced the factory to rubble, shook nearby buildings and blew out windows.

Most of the casualties were female workers who were assembling fuses for firecrackers, the Xinhua News Agency said.

The cause of the explosion is not known.

Two factory executives have been detained, according to the Guangxi Work Safety Bureau.

Wang Dexue, deputy head of the State Administration of Work Safety, told China Daily earlier this year that workplace safety was a major problem in China as negligence by local work safety supervisors has led to frequent industrial accidents in the country, particularly in the mining industry.

A total of 27,700 people died or went missing in workplace accidents in the first half of this year, according to state authorities.

A fire that killed 119 people at a poultry plant in Northeast China's Jilin province in June raised concerns about work safety conditions and led to a nationwide work safety overhaul.

According to a recent study by the Supplier Ethical Data Exchange (SEDEX) , however, Romania has the worst industrial fire safety compliance in the world.

The findings showed that in Romania, 33.2% of health and safety non-compliance issues related to fire safety, the highest percentage of any country. Portugal followed with 25%, then the US and Czech Republic with 24.2% and 22.7% respectively, and Italy with 20.1%.

By region, the report revealed Europe has the highest proportion of fire safety issues, with 13.5% of non-compliance matters relating to fire. Next was Asia with 12.7%, then South America and North America. Africa had the lowest, with only 6.6%.

Mark Robertson, a spokesman for Sedex, which promotes responsible and ethical business practices within global supply chains, said: "Investors need to understand that such risks and hazards do not take place only in developing countries. They must take a proactive stance and engage with companies in all areas."