The picture taken on July 14, 2014, shows two burned cars in Tripoli International Airport, in Libya. Armed clashes broke out at Libya's international airport in Tripoli the previous day, leaving nine people dead and 25 others injured. [Photo/Xinhua]

TRIPOLI - Libya's international airport in capital Tripoli came under renewed attack on Monday with dozens of rocket-propelled grenades attacking planes and tarmacs, according to security sources.

One witness in southern Tripoli said intense gunfire and explosions could be heard and heavy smoke rose from different sites.

The fighting, starting from early Sunday, was between Islamist militant groups and militias from southwestern city of Zintan who has been guarding the crucial air hub since the toppling of Libya' s former leader Muammar Gaddafi.

Medical sources said the clashes has so far killed nine and injured more than 30.

The Islamist militant groups, some affiliated with the government, said that their goal was to expel all militias from Tripoli in a militarized operation dubbed "Libya Dawn."

However, the Libyan government issued a statement on Sunday afternoon, condemning the move as "illegitimate."

Tripoli International Airport and Misrata airport have now suspended their operation due to security reasons.

Meanwhile, the Civil Aviation Authority also suspended all flights to Tripoli for the next three days and will dispatch a team to monitor the situation.

Libya has witnessed a drastic escalation of violence and political instability since the fall of Gaddafi's government. Libya's weak central government has failed to reign in the former rebels and militias, many of whom now operate with impunity.