A 60-year-old woman with the last name Xiang told AFP that she had long been worried about the safety of the plant.

"We knew we'd be blown up one day," she said.

The blast caused fires to ignite in the industrial park where the plant was located, but firefighters said they had extinguished the flames by Friday. Hundreds of rescue workers had been sent to the area, according to local authorities.

However, residents in the surrounding area, many of them elderly, said they had not received any help from the government. Some had abandoned their homes and others were sweeping up the glass from broken windows themselves.

The plant where the explosion occurred was run by the Jiangsu Tianjiayi Chemical company, which produces more than 30 organic chemical compounds, according to Sky. In February of last year, China's State Administration for Work Safety found 13 safety hazards at the company, including improper handling of benzene, the chemical that caused Thursday's explosion. In total, the company had amassed 1,790,000 RMB (approximately $266,440) in fines since 2016 because of environmental violations.

The cause of Thursday's explosion is not yet known. Chinese President Xi Jinping, currently on a state visit to Italy, urged for "all-out efforts" to rescue those still trapped in collapsed buildings and for the cause of the incident be determined "as early as possible," AFP reported in a later article. Local authorities looking into the explosion said an undetermined number of people had been taken into custody on Friday.

Nearby residents are now concerned about the spread of pollution following the accident.

"We don't have drinkable water here," Xiang told AFP. "Why hasn't the government sent us some water?"

However, local environmental agencies said that they had set up monitors around the industrial park where the accident took place, and said that strong winds looked likely to flush out toxins in the air, CNN reported.

China has suffered a spate of industrial and mining disasters in its recent history, partly because of weak safety enforcement, BBC News reported. The largest in the last few years was a 2015 explosion in Tianjin that killed more than 160 and injured almost 1,000.