How devastating was the Beirut explosion?

In Lebanon rescuers in Beirut are searching for survivors after two explosions left much of the city in ruins. The blasts happened at a warehouse where tonnes of the highly explosive chemical ammonium nitrate were stored, apparently without any safety measures. At least 100 people were killed and thousands injured. Authorities have placed a number of Beirut port officials under house arrest. The government has declared a two-week state of emergency for the city.