“The accident demonstrates that some local governments and companies in Jiangsu province did not take past accidents seriously and did not invest solidly in improving security measures,” the team said in a statement on the ministry’s official Weibo account.

“They just continued with their deeds and it resulted in tragedy,” it said.

The announcement came after the team, led by the ministry’s party secretary Huang Ming, met for the first time on Saturday.

There have previously been small explosions at the industrial park in Xiangshui county, Yancheng. Eight people were killed in a blast at the park not long after it opened in 2007.

Xu Mei, whose father lives in nearby Wangshang, said local residents were aware of the danger but the factories in the park provided them with a financial lifeline so they took the risk.

“There have been small blasts before,” Xu said. “We all know it’s dangerous but we never expected something this bad could happen. The factories also provide us with jobs and improve our situation.”

Xu said she had decided to move further out, but her father had remained in Wangshang, a village located just 1km from the park.

Zhu Xiaoying, who is also from Wangshang, described the industrial park as a “time bomb” and said the government had insisted on building it close to the residential area.

“When the industrial park was built around 2007, I knew it was a time bomb. We voiced our opposition but it didn’t work, so we moved far away,” Zhu said. “Now something terrible has finally happened.”

The investigators sent by the State Council have vowed to determine the cause of the blast as soon as possible, and called for an immediate improvement in safety standards and accident prevention procedures at similar parks across the country.

Survivors relive horror of ‘earth-shattering’ blast

Meanwhile, internet users have been sharing an article written in 2011 by a China Youth Daily reporter that alleges the Xiangshui district government tried to cover up the deadly 2007 blast.

The piece, written by Li Runwen, who was at the scene, said the authorities went to extraordinary lengths to prevent journalists from covering the story.

“The Yancheng government had an emergency plan, using force, locking the reporters up [in hotels], trying to buy them off with cash and even seducing them [with prostitutes],” it said.

On Saturday, wards at the two biggest hospitals in Xiangshui county – Xiangshui People’s Hospital and Xiangshui Hospital of Traditional Chinese Medicine – were packed with people who were injured in the blast, while other patients were on beds in the hallways.

Liu Yujian, who was working at nearby Jiangsu Lianhua Technology at the time of the blast, said he was aware of the safety issues at the industrial park, including the explosion in 2007.

“But sometimes you just can’t avoid it – it’s the same with pollution,” Liu said from a bed at the Xiangshui Hospital of Traditional Chinese Medicine.

The 26-year-old had to get stitches after he was hit in the face by glass from a window that shattered in the blast. “The doctor told me there will be a long scar [on my nose] – it looks very bad,” he said.

Another patient, surnamed Yang, was working in a factory about 400 metres from the blast site. Her back and feet were injured in the explosion, and for now all she can think about is rest and recovery.

“I’ll stay here for three or four days hopefully, then I can go home,” she said. “Some of the factory bosses have visited me but they didn’t say much – I think it’s a bit early to talk about compensation.”

As the rescue effort continued, China’s state broadcaster on Saturday published video footage on social media of firefighters carrying a man to safety from the scene of Thursday’s explosion.

The post provided few details of the rescue except to say that the man had been trapped for 40 hours, which suggests he was found in the early hours of Saturday morning.

The video footage – posted on Weibo, China’s Twitter-like platform – shows a firefighter carrying the man on his back through the rubble and debris which is all that remains of many of the buildings on the site. The report said he was found inside the Zhijiang chemical factory, about 500 metres from the site of the initial blast.

Yancheng mayor Cao Lubao told a news conference on Saturday morning that officials were still trying to account for the whereabouts of 28 people, but that it was unclear if they were missing or among the fatalities that had not yet been identified.

Local police are continuing to gather information about the case and have established a hotline to help those whose loved ones are still missing.

Cao said those responsible for the accident would feel the full weight of the law.