The explosion on Tuesday sent shockwaves across the city, causing widespread damage as far as the outskirts of the capital.
Officials said they expect the death toll to rise further as emergency workers dig through the rubble to search for survivors.
Beirut’s city governor Marwan Abboud said between 200,000 and 250,000 people had lost their homes and authorities are working on providing them with food, water and shelter.
The cause of the explosion was not immediately clear. Officials linked the blast to some 2,750 tonnes of confiscated ammonium nitrate that were being stored in a warehouse at the port for six years.