A series of enormous explosions at an industrial area in the Chinese port of Tianjin has killed at least 44 people and injured more than 500, unleashing a fireball that ripped through the night sky.
An AFP reporter at the scene saw shattered glass up to three kilometres from the blast site, after a shipment of explosives detonated in a warehouse on Thursday (local time), raining debris on the city and starting huge fires.
Images showed a monumental blast soaring into the air, walls of flame enveloping buildings, ranks of burned-out cars, and shipping containers scattered like children's building blocks.
Paramedics stretchered the wounded into the city's hospitals as doctors bandaged up victims, many of them covered in blood after the impact of the explosion was felt for several kilometres, even being picked up by a Japanese weather satellite.
"The fireball was huge, maybe as much as 100 metres tall," said 27-year-old Huang Shiting, who lives close to the site.
"I heard the first explosion and everyone went outside, then there was a series of more explosions, windows shattered and a lot of people who were inside were hurt and came running out, bleeding," he said.
Images showed residents, some partially clothed, running for shelter on a street strewn with debris.
Citing rescue headquarters, the official Xinhua news agency said 44 people were killed, including 12 firefighters.
Scores of firefighters were already on the scene before the explosion, responding to reports of a fire, and at one city hospital a doctor wept over the remains of a firefighter still in uniform, his skin blackened from smoke, as he was wheeled past, along with two other bodies.
Xinhua said 520 people had been hospitalised, 66 of them in critical condition.
Mei Xiaoya, 10, and her mother were turned away from the first hospital they went to because there were too many people, she said.
All the windows of her home and the door were destroyed in the explosion, she said.
"I'm not afraid, it's just a scratch," she said pointing to the bandage on her arm. "But mum was hurt badly, she couldn't open her eyes."
Plumes of smoke still billowed over buildings hours after the blast, which occurred shortly before midnight local time.
Communist Party newspaper the People's Daily said in a social media post that there were people trapped by the fire, but CCTV said efforts to put out the blaze had been suspended as it was not clear what dangerous items remained in the storage facility.
Specialised anti-chemical warfare troops were being sent to the site, the broadcaster added.
It was not clear what caused the shipment of explosives to detonate inside a storage container.
The magnitude of the first explosion was the equivalent of detonating three tonnes of TNT, the China Earthquake Networks Centre said on its verified Weibo account, followed by a second blast equal to 21 tonnes.
Police took into custody the head of the company involved, Tianjin Dongjiang Port Rui Hai International Logistics, local authorities said.