Tianjin explosion: Dozens dead, areas of Chinese port city devastated

Updated 11:27 PM EDT, Thu August 13, 2015
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A resident injured by the explosions that hit a nearby chemical warehouse last week holds a photo of herself injured as she joins a protest outside the hotel where authorities are holding a press conferences in Tianjin on August 17, 2015. Rescuers at a Chinese industrial site where huge explosions killed at least 114 people combed through thousands of crushed shipping containers on August 17 in an effort to contain vast amounts of highly toxic cyanide, officials said, as state-run media lambasted authorities for their response to the tragedy. CHINA OUT AFP PHOTOSTR/AFP/Getty Images
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A resident injured by the explosions that hit a nearby chemical warehouse last week holds a photo of herself injured as she joins a protest outside the hotel where authorities are holding a press conferences in Tianjin on August 17, 2015. Rescuers at a Chinese industrial site where huge explosions killed at least 114 people combed through thousands of crushed shipping containers on August 17 in an effort to contain vast amounts of highly toxic cyanide, officials said, as state-run media lambasted authorities for their response to the tragedy. CHINA OUT AFP PHOTOSTR/AFP/Getty Images
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A woman (C) holds a name list of missing firefighters as family members talk to media to seek for help after being barred from a press conference authorities have at a hotel in Tianjin on August 15, 2015. Furious, frustrated and fearful, relatives of the missing in giant explosions in Tianjin besieged officials on August 15 demanding answers on their loved ones's fates- only for security to intervene instead.CHINA OUT     AFP PHOTO        (Photo credit should read STR/AFP/Getty Images)
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A woman (C) holds a name list of missing firefighters as family members talk to media to seek for help after being barred from a press conference authorities have at a hotel in Tianjin on August 15, 2015. Furious, frustrated and fearful, relatives of the missing in giant explosions in Tianjin besieged officials on August 15 demanding answers on their loved ones's fates- only for security to intervene instead.CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)
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A damaged car is seen at the site of the massive explosions in Tianjin on August 13, 2015. Enormous explosions in a major Chinese port city killed at least 44 people and injured more than 500, state media reported on August 13, leaving a devastated industrial landscape of incinerated cars, toppled shipping containers and burnt-out buildings. CHINA OUT AFP PHOTOSTR/AFP/Getty Images
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A damaged car is seen at the site of the massive explosions in Tianjin on August 13, 2015. Enormous explosions in a major Chinese port city killed at least 44 people and injured more than 500, state media reported on August 13, leaving a devastated industrial landscape of incinerated cars, toppled shipping containers and burnt-out buildings. CHINA OUT AFP PHOTOSTR/AFP/Getty Images
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An explosion took place in China's northern city of Tianjin late Wednesday, August 12, 2015 evening, according to China's state-owned broadcaster CCTV. The explosion occurred at a container port where flammable material was being stored in containers, says CCTV. Residents report hearing loud explosions and feeling strong tremors nearby. The Teda Hospital, located near the scene of explosion, has received more than 50 injured people, the country's state-run Xinhua news agency reported.
Chinese Public Security Ministry
An explosion took place in China's northern city of Tianjin late Wednesday, August 12, 2015 evening, according to China's state-owned broadcaster CCTV. The explosion occurred at a container port where flammable material was being stored in containers, says CCTV. Residents report hearing loud explosions and feeling strong tremors nearby. The Teda Hospital, located near the scene of explosion, has received more than 50 injured people, the country's state-run Xinhua news agency reported.
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Story highlights

NEW: Chemical specialists from the military have been sent in the area

NEW: More than 700 people have been hospitalized, dozens with critical injuries

Dozens of people remain missing

(CNN) —  

You can see the devastation everywhere: in the hollowed-out shells of buildings, in the anguished faces of relatives, in the parade of scorched cars.

But what set off the terrifying explosions that ripped through warehouses containing hazardous chemical materials, shooting fireballs across the sky and shaking buildings more than 2 miles away?

Hours later, amid the destruction in this northern Chinese port city of more than 13 million people, the cause of Wednesday night’s blast remained unclear.