Massive explosions have hit China's northern port city of Tianjin, reportedly injuring many people.

According to Chinese state media, the blasts occurred when a shipment of explosives blew up at about 23:30 (16:30 GMT).

Pictures and video shared on social media showed flames lighting up the sky and damage to nearby buildings.

Latest reports in state media suggest that hundreds of people have been taken to hospital.

The first explosion was followed by another 30 seconds later. Further blasts were subsequently triggered nearby, Xinhua state news agency said.

Shockwaves could apparently be felt several kilometres away from Tianjin.

The Editor of the BBC's Chinese Service, Raymond Li, says all indications are that it is an industrial accident.

Ms Yang, an eyewitness, told local media she was out shopping when "suddenly from behind there was a big fireball and explosion".

"At the time of the explosion the ground was shaking fiercely, nearby cars and buildings were shaking, a few buildings' glass all broke and everyone started to run," she said. "Now all the residents are gathered in the street."

China National Radio said cracks were visible in buildings near the site of the blast. Several tower blocks near the port area are without power, reported the Chinese state broadcaster CCTV.

The blasts took place in a warehouse area storing dangerous goods in Tianjin's Binhai development zone, Xinhua said.