Video Emerges of Horrific Tianjin Explosion as Death Toll Rises

The massive explosion in Chinese port city Tianjin on Wednesday caused apocalyptic scenes, including massive fireballs that turned the night sky into day. In the aftermath the death count is continuing to increase — at least 44 people were killed, while hundreds were injured.

Of those who died, 12 were firefighters, according to the municipal government. More than 1,000 firefighters were sent to fight the blaze set off by the explosions shortly before midnight. Officials also said 520 people were being treated in hospitals, 66 of them with serious injuries. They gave no figure for the missing.

The blasts, originating at a warehouse for hazardous material, turned buildings in the immediate vicinity into charred shells while shattering windows up to several miles away.

Related: In Photos: The Aftermath of the Massive Explosion in the Chinese City of Tianjin

"I thought it was an earthquake, so I rushed downstairs without my shoes on," said Tianjin resident Zhang Siyu, whose home is several miles from the blast site. "Only once I was outside did I realize it was an explosion. There was the huge fireball in the sky with thick clouds. Everybody could see it."

Zhang said she could see wounded people weeping. She said she did not see anyone who had been killed, but "I could feel death."

An injured firefighter receives treatment. At least twelve firefighters were dead at — China Xinhua News (@XHNews)August 13, 2015

There was no indication of what caused the blasts, and no immediate sign of any large release of toxic chemicals into the air. Beijing News said there was some unidentified yellow foam on the ground at the site, although it was not clear if this was contamination or part of the fire-fighting efforts.

The ensuing fire was mostly under control by morning, and the Tianjin local government said further firefighting was suspended on orders of the central government so that a team of chemical experts can assess hazardous materials on site, dangers to the environment and how best to proceed with putting out the rest of the fire.

"It was like what we were told a nuclear bomb would be like," said truck driver Zhao Zhencheng, who spent the night in the cab of his truck after the blasts. "I've never even thought I'd see such a thing. It was terrifying, but also beautiful."

Aerial view of the explosion site of Tianjin massive blasts.  Death toll has climbed to 44 — China Xinhua News (@XHNews)August 13, 2015

Police in Tianjin said an initial blast took place at shipping containers in a warehouse for hazardous materials owned by Ruihai Logistics, a company that says it is properly approved to handle such materials. State media said senior management of the company had been detained by authorities, and that President Xi Jinping has demanded severe punishment for anyone found responsible for the explosions.

The website of the logistics company became inaccessible Thursday.

The Tianjin government also said that because of the blasts it had suspended online access to public corporate records. These records might be used to trace the ownership of Ruihai. It was not clear whether the blackout was due to technical damage related to the explosion. No one answered the phone at the Tianjin Market and Quality Supervision Administration or the Tianjin Administration for Industry and Commerce Thursday.

Related: 13 Reported Dead as New Video Emerges of Explosion In China

The explosions took place in a mostly industrial economic development zone, with some apartment buildings in the vicinity. Buildings of a half-dozen other logistics companies were destroyed in the blasts, and more than 1,000 new cars were left charred in a nearby parking lot, the Beijing News said.

The initial blast apparently triggered at least one further blast. The National Earthquake Bureau reported two major blasts before midnight, the first with an equivalent of 3 tons of TNT, and the second with the equivalent of 21 tons.

About 1.2 miles from the explosion site is the luxury Fifth Avenue apartment complex on a road strewn with broken glass and pieces of charred metal thrown from explosion. Like surrounding buildings, the Mediterranean style complex had all its windows blown out, and some of its surfaces were scorched.

"It's lucky no one had moved in," said a worker on the site, Liu Junwei, 29. "But for us it's a total loss. Two years of hard work down the drain."

"It had been all quiet, then the sky just lit up brighter than day and it looked like a fireworks show," said another worker on the site who gave just his surname, Li.

Tianjin, with a population of about 15 million, is about 120 kilometers (75 miles) east of Beijing on the Bohai Sea and is one of the country's major ports. It is one of China's more modern cities and is connected to the capital by a high speed rail line.

The Associated Press contributed to this report.