Injured people were walking in the street, while outside the Clemenceau Medical Centre, dozens of wounded people, many covered in blood, were rushing to be admitted to the center including children.
A soldier at the port, who asked not to be named, told AFP: “It’s a catastrophe inside. There are corpses on the ground. Ambulances are still lifting the dead.”
Destroyed cars had been abandoned in the street with their airbags inflated.
A huge cloud of black smoke was engulfing the entire port area, the AFP correspondent said.
The loud blasts in Beirut’s port area were felt across the city and beyond and some districts lost electricity.
“Buildings are shaking,” tweeted one resident, while another wrote: “An enormous, deafening explosion just engulfed Beirut. Heard it from miles away.”
Online footage from a Lebanese newspaper office showed blown out windows, scattered furniture and demolished interior panelling.
The explosions came at a time when Lebanon is suffering its worst economic crisis in decades, which has left nearly half of the population in poverty.
Lebanon’s economy has collapsed in recent months, with the local currency plummeting against the dollar, businesses closing en masse and poverty soaring at the same alarming rate as unemployment.
The explosions also come as Lebanon awaits the verdict on Friday on the 2005 murder of former Lebanese premier Rafic Hariri, killed in a huge truck bomb attack.
Four alleged members of the Shiite Muslim fundamentalist group Hezbollah are on trial in absentia at the court in the Netherlands over the huge Beirut suicide bombing that killed Sunni billionaire Hariri and 21 other people.
A woman in the city center told AFP: “It felt like an earthquake … I felt it was bigger than the explosion in the assassination of Rafic Hariri in 2005”.
Tensions have also been high with neighboring Israel, after Israel said it thwarted an infiltration attempt by up to five Hezbollah gunmen, a claim denied by the Iran-backed group.