BEIRUT, Lebanon

Lebanese Minister of Public Works and Transport Michael Najjar said on Wednesday the explosion at the Port of Beirut has caused massive damage and destroyed most of the port's facilities and warehouses.

Speaking to Lebanese local channel "LBC", Najjar said the Lebanese authorities have started to set alternative plans for the Beirut port, which will take time to be rebuilt.

"We will depend on the Tripoli port in northern Lebanon, as we are currently evaluating its capacity along with other ports in Sidon and Tyre,” he said.

On Tuesday, a massive explosion rocked the port, killing at least 100 and injuring 4,000 others and caused massive damage in several neighborhoods of the capital.

Prime Minister Hassan Diab announced Wednesday a day of mourning and promised "those responsible for this catastrophe will pay the price". Diab also appealed for international assistance to help afflicted Lebanon.

Following the deadly blast, the Lebanese Supreme Defense Council has declared a state of emergency for two weeks in Beirut. The capital was also declared a "disaster area" due to the incident.

The explosion took place as Lebanon's economy was facing its worst crisis in decades. It also happened days before the announcement of a verdict on Friday by the UN-backed court in the case of killing former Prime Minister Rafik al-Hariri.

*Ahmed Asmar contributed to this report from Ankara