At least 728 people have been wounded in clashes with authorities as thousands of protesters hit the streets of central Beirut as riot police fire tear gas at those trying to break through a barrier to the parliament building, Al Jazeera reported.

One police officer was also reported killed.

Lebanon's Prime Minister Hassan Diab has called for early polls after Tuesday's deadly blast, saying it is the only way out of the country's crisis.

Lebanese authorities have taken into custody 19 people as part of an investigation.

At least 158 people were killed in the explosion and more than 6,000 others injured, but numbers are expected to rise as search and rescue operations continue for missing people.

The demonstrators, in particular, accused the ruling coalition of corruption, and demanded early elections and an independent investigation into Tuesday’s blast in the port of Beirut.