Beirut has been rocked by a huge explosion, devastating parts of the city and injuring thousands of people. Eyewitness footage shared widely on social media showed a section of the city's port area on fire before a huge blast engulfed nearby neighbourhoods, flattening buildings and leaving streets littered with broken glass and debris.

The Lebanese security chief, Abbas Ibrahim, later blamed combustible chemicals stored in a warehouse. Lebanon's prime minister, Hassan Diab, said those responsible would 'pay a price' for the disaster.

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Lebanese capital in state of chaos as people grapple with scale of blast that has injured thousands

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As a ghostly brown haze began to clear, the streets of east Beirut emerged in apocalyptic ruin. Even 4km from the centre of the blast each building had lost some, if not all, of its windows. It was just after 6pm. Smoke, dispersed with pockets of pink gas, shrouded some of the carnage. Huge shards of glass covered roads – some jagged pieces had ripped through cars. Trees were shredded, and pools of blood formed puddles in the streets.

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Video circulating on social media shows a massive explosion rocking central Beirut - shattering windows, knocking down doors and shaking buildings several hundred feet away. 

Lebanon’s health minister told journalists a ship carrying fireworks had blown up in the port, though the size of the blast heard across the country raised suspicions it might have resulted from a rocket strike or detonation of explosives - deliberate or otherwise. The source of the blast has not been confirmed

• Beirut explosion – live updates