TIANJIN, China, Aug. 13 (UPI) -- Authorities are investigating a series of powerful explosions that rocked a port city in China late Wednesday -- killing at least 17 people and injuring hundreds more, officials said.
Officials ordered a rapid rescue effort immediately after the blasts, which occurred in seaside Tianjin. Authorities are still trying to determine the cause of the explosions but Chinese President Xi Jinping has already promised harsh punishment if it's determined they were intentional, NBC News reported late Wednesday.
Two powerful blasts occurred before midnight local time, state news agency Xinhua reported, at a warehouse that housed "dangerous and chemical goods."
Government officials said the initial firefighting efforts were hampered due to uncertainty over what materials or chemicals were stored inside.
So far, 17 people have died from the explosions and various media reported at least 238 were hurt -- nearly three dozen of them critically, NBC reported. Some reports cited more than 400 wounded and firefighters among the dead.
The explosions registered on earthquake equipment in the area -- the second, and most powerful, explosion was measured at a magnitude of 2.9, the equivalent of 21 tons of TNT.
"I thought it was an earthquake, so I rushed downstairs without my shoes on," Tianjin resident Zhang Siyu told Fox News. "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.
"I could feel death."
One surveillance video taken at the moment of one explosion showed a bystander blasted back by an avalanche of debris -- a scene that might look more like special effects from a disaster movie than reality.
Photographs and video taken in the aftermath of the blasts showed large-scale damage to infrastructure and a lot full of brand new vehicles. Several buildings collapsed due to the explosions, state news media reported.
"I express my deep condolences for the tragic loss of life and the hundreds injured in the Tianjin explosions," said British Foreign Secretary Philip Hammond, who was visiting Beijing, about 100 miles northwest of Tianjin.
In addition to the dead and injured, numerous people remain unaccounted for amid the wreckage and rapid rescue crews are working furiously to try and render aid to those who have survived.