Anger mounted in Lebanon on Wednesday as rescuers searched for survivors of a cataclysmic explosion at Beirut port that wreaked destruction across the city, killing at least 113 people, wounding thousands and plunging crisis-striken Lebanon further into the abyss.

The blast on Tuesday, apparently triggered by a fire igniting 2,750 tonnes of ammonium nitrate fertiliser left unsecured in a warehouse of Beirut port, was heard as far as Cyprus, some 150 miles (240 kilometres) away.

It struck the Lebanese capital like an earthquake, with dozens still missing on Wednesday, thousands of people left destitute and thousands more cramming into overwhelmed hospitals for treatment.

A helicopter pours water onto the fire at the port of Lebanon's capital Beirut
A helicopter pours water onto the fire at the port of Lebanon's capital Beirut AFP / STR

One doctor, his own head bandaged like those of his patients, described the scene as "Armageddon".

"Wounded people bleeding out in the middle of the street, others lying on the ground in the hospital courtyard," said Dr Antoine Qurban outside Hotel Dieu Hospital in central Beirut.

And as volunteers led the clear-up effort, public outrage mounted over how such a vast haul of highly combustible material -- sometimes used for homemade bombs -- had been stored next to a densely populated area for at least six years.

The government vowed to investigate and cabinet urged the military to place those responsible for storing the substance under house arrest.

Lebanese firefighters evacuate a wounded man across the rubble of buildings flattened by the force of the monster blast in Beirut port
Lebanese firefighters evacuate a wounded man across the rubble of buildings flattened by the force of the monster blast in Beirut port AFP / Anwar AMRO

But Lina Daoud, a 45-year-old resident of the devastated Mar Mikhail district where the explosion had strewn bodies in the street, blasted the country's politicians as "enemies of the state".

"They killed our dreams, our future," she said. "Lebanon was a heaven, they have made it hell."

An initial explosion and fire at the port had sent many people to balconies and rooftops where they were filming when the fertiliser exploded, sending out a massive shockwave across the city.

In an instant, the blast left destruction likened to that caused by the country's 1975-1990 civil war, levelling buildings several hundred metres (yards) away.

An injured man lies at the back of a car before being rushed away from the scene of a massive explosion at the port
An injured man lies at the back of a car before being rushed away from the scene of a massive explosion at the port AFP / Marwan TAHTAH

City mayor Abboud said the devastation may have left 300,000 people temporarily homeless, adding to the cash-strapped country's economic misery with an estimated $3 billion in damages.

"Even in the worst years of the civil war, we didn't see so much damage over such a large area," said analyst Kamal Tarabey.

The blast in Beirut's port area sent a huge plume of smoke into the sky
The blast in Beirut's port area sent a huge plume of smoke into the sky AFP / Anwar AMRO

The disaster came with Lebanon already on its knees with a months-long economic crisis and currency devaluation sparking spiralling poverty even before the coronavirus pandemic hit.

The embattled government of Prime Minister Hassan Diab vowed that "those responsible for this catastrophe will pay the price".

The ammonium nitrate had been stored in a rundown port warehouse with cracks in its walls, officials told AFP.

The blast which rattled entire buildings was felt across the city and far beyond
The blast which rattled entire buildings was felt across the city and far beyond AFP / Anwar AMRO

Security forces launched an investigation in 2019 after the warehouse started to exude a strange odour, concluding the "dangerous" chemicals needed to be removed, but action was not taken.

Analyst and Georgetown University professor Faysal Itani was not optimistic that anybody would be held accountable.

"There is a pervasive culture of negligence, petty corruption and blame-shifting endemic to the Lebanese bureaucracy, all overseen by a political class defined by its incompetence and contempt for the public good," he wrote in a New York Times op-ed.

"These politicians are well practiced in shifting the blame."

The huge numbers of wounded quickly overwhelmed Beirut's hospitals
The huge numbers of wounded quickly overwhelmed Beirut's hospitals AFP / IBRAHIM AMRO

Messages of support poured in from around the world, including Britain's Queen Elizabeth who said she was "deeply saddened" by the disaster.

France said it would send three planes of aid, followed by a visit Thursday by President Emmanuel Macron.

US Secretary of State Mike Pompeo offered assistance, while Defense Secretary Mark Esper played down President Donald Trump's earlier suggestion that a bomb had been responsible.

"Most believe that it was an accident as reported," Esper told the Aspen Security Forum.

IMAGESBeirut awoke on Wednesday morning to the aftermath of two enormous explosions that ripped through Beirut's port, killing at least 78 people and injuring thousands.
IMAGESBeirut awoke on Wednesday morning to the aftermath of two enormous explosions that ripped through Beirut's port, killing at least 78 people and injuring thousands. AFPTV / Abir AL AHMAR

The UN's Food and Agriculture Organization warned Wednesday that the destruction of the port and grain silos would cause critical severe flour shortages, in a country heavily reliant on imports.

Social media user voiced outrage at the government, saying such a disaster could only strike because of the ineptitude and corruption riddling Lebanon's institutions.

Hospitals already stretched to the brink by a spike in coronavirus cases were pushed to new limits by the influx of wounded and were forced to turn many away.

Lebanon has recorded 5,417 cases of COVID-19, including 68 deaths.

"We've had some dark days in Lebanon over the years but this is something else," said Rami Rifai, a 38-year-old engineer.

He spoke to AFP from a hospital where his two daughters were receiving treatment after sustaining cuts despite being half a kilometre from the seat of the blast.

"We already had the economic crisis, a government of thieves and coronavirus. I didn't think it could get worse but now I don't know if this country can get up again," he said.

In the Netherlands, a UN-backed tribunal said it had suspended a verdict on the 2005 murder in a huge Beirut bomb blast of former Lebanese premier Rafic Hariri, scheduled for Friday, following the latest carnage.