Over 100 people have died and more than 4,000 injured in the graphic blast that occurred in Lebanon yesterday.

It has been claimed that the huge explosion in Beirut, Lebanon was caused by a welder at work.

Close to where the welder was working, there was “highly explosive sodium nitrate” confiscated from a ship by Lebanese authorities and placed in one of the warehouses located near the harbour. The ammonium nitrate – more than 2,750 tons – had been stored in the warehouse for six years.

Security sources in the country have claimed the welder sparked the initial fire that in turn ignited the chemicals, causing a blast that has been compared to a “nuclear bomb”.

The blast sent seismic shockwaves through the city on Tuesday evening, August 4, destroying buildings and shattering windows.

Over 100 people died in the blast and more than 4,000 sustained varying degrees of injuries.

Many people are feared to still be trapped under the rubble, including those trapped inside their damaged homes.

As at this morning, smoke was still rising from the port, where a towering grain silo was shattered. Toxic gases were been reported in the aftermath along with strange orange clouds, with the US Embassy warning any Americans in Beirut to stay inside.

The head of Lebanon’s Red Cross said: “What we are witnessing is a huge catastrophe. There are victims and casualties everywhere.”

Ammonium nitrate is mainly used as a fertilizer but has also been linked to terror attacks after being used in homemade bombs.

General Security chief Abbas Ibrahim said it had been confiscated years earlier, reportedly from a ship.

Lebanese President Michel Aoun has declared a state of emergency for Beirut for two weeks – and vowed the “harshest punishments” for those responsible for causing the explosion.

Prime Minister Hassan Diab described the disaster as a “national catastrophe” and added that “those responsible will pay the price”.

His wife and daughter were injured in the explosion after it damaged his residence at The Government Palace.