Trump: Massive explosion in Beirut was likely an 'attack'

President Donald Trump said US military generals have told him that they think the massive explosion that rocked Beirut on Tuesday, killing more than 70 people, was likely a bomb.

"I've met with some of our great generals and they just seem to feel that this was not some kind of manufacturing explosion type of an event ... They seem to think it was an attack. It was a bomb of some kind."

The explosion flattened much of a port and damaged buildings across the capital, sending a giant mushroom cloud into the sky. The death toll, which currently stands at more than 70, and more than 3000 others were injured, with bodies buried in the rubble, officials said.

President Donald Trump speaks during a briefing with reporters in the James Brady Press Briefing Room of the White House. Photo / AP

Hours later, ambulances still carried away the wounded as army helicopters helped battle fires raging at the port.

The sudden devastation overwhelmed a country already struggling with both the coronavirus pandemic and an economic crisis: Beirut hospitals quickly filled beyond capacity, pleading for blood supplies and generators to keep their lights on.

Lebanese officials earlier said the cause of the blast, which sparked fires, overturned cars and blew out windows and doors, was not immediately known.

Abbas Ibrahim, chief of Lebanese General Security, said it might have been caused by highly explosive material that was confiscated from a ship some time ago and stored at the port. Local television channel LBC said the material was sodium nitrate.

An injured man walks at the explosion scene that hit the seaport, in Beirut Lebanon. Photo / AP

Witnesses reported seeing a strange orange-coloured cloud over the site after the explosion. Orange clouds of toxic nitrogen dioxide gas often accompany an explosion involving nitrates.

An Israeli government official said Israel "had nothing to do" with the blast. He spoke on condition of anonymity because he was not authorised to discuss the matter with the media. Israeli officials usually do not comment on "foreign reports".

The blast was stunning even for a city that has seen civil war, suicide bombings and bombardment by Israel. It could be heard and felt as far away as Cyprus, more than 200km across the Mediterranean Sea.

"It was a real horror show. I haven't seen anything like that since the days of the [civil] war," said Marwan Ramadan, who was about 500 metres from the port and was knocked off his feet by the force of the explosion.

-Associated Press