About 6:30 pm local time, two large explosions took place in the port of the Lebanese capital Beirut.
The car crashed into fire and the buildings collapsed due to the shock and heat of the explosion.
The impact of the explosion was equivalent to an earthquake of magnitude 4.5, smashing the windows of a building 10 km away.
The Lebanese Ministry of Health says 73 people have been killed and 3,700 wounded in the explosion.
[Paris Sharawi/Beirut Citizen: When I heard the explosion, I went to see what happened, but there was an unexpected second explosion. The window exploded in front of me. ]
Lebanese Prime Minister Hassan Diab says 2,750 tonnes of ammonium nitrate have been stored in the explosive warehouse in Beirut for six years without any safety measures.
The explosion of ammonium nitrate has been observed to impact all over Beirut.
Ammonium nitrate, an agricultural fertilizer, explodes easily when in contact with flammable materials and is used as a basic raw material for inorganic production.
Lebanese President Michel Aun declared a two-week emergency in Beirut, and officials say they will be punished strongly.
The embassy of Lebanon, 7.3 km from the site of the accident, says two glass windows on the 4th floor of the embassy building have been broken, but no casualties have been reported.