Libyan rebels say they have captured Misrata airport, driving back troops loyal to Col Muammar Gaddafi.
Hundreds of rebels were celebrating in the streets after pro-Gaddafi forces fled, leaving behind tanks that were set on fire, witnesses said.
Government forces have been pounding the western city, which remains largely under rebel control, for weeks.
Meanwhile, Libya's state TV showed footage of Col Gaddafi meeting tribal leaders in the capital Tripoli.
The video was shot on Wednesday evening, a Libyan official told the AFP news agency. This has not been independently verified.
Col Gaddafi has not appeared in public since 30 April - when a Nato air strike killed his youngest son, 29-year-old Saif al-Arab, and three of his grandchildren.
Fresh explosions were reported in the capital Tripoli on Wednesday.
Nato said earlier that its planes had carried out 6,000 missions over Libya since it assumed command of military operations there at the end of March.
The air strikes have helped secure rebels in their strongholds in eastern Libya, but observers say it remains unclear to what extent they have loosened Col Gaddafi's grip on the west of the country.
Bodies in street
Witnesses said Misrata airport fell after hours of fighting between rebels and pro-Gaddafi forces overnight.
The bodies of pro-government forces could be seen lying in the street as the rebels celebrated their victory, correspondents said. A dozen rebels were said to have been wounded in the fighting.
Col Ahmed Bani, a spokesmen for the rebel leadership in Benghazi, told the BBC that as well as taking the airport, "revolutionary forces" now controlled Misrata.
As well as burning government tanks, the rebels had captured other weaponry from the regime troops, he said.
Libya's third-largest city, Misrata is the only significant western rebel holdout and is strategically important because of its deep-sea port, which has become a lifeline for supplying civilians and for evacuating wounded people fleeing the fighting.
Though the rebels are said to be better organised than those in eastern Libya and have, for example, set up a network of makeshift arms factories, their campaign is still an improvised affair.
Government forces have sown anti-shipping mines off the harbour, used Russian-made Grad rockets to scatter anti-vehicle mines in the port, and set fuel storage tanks ablaze with missile strikes, according to rebels and human rights groups.
Pro-Gaddafi troops in civilian areas are also using Spanish-made cluster bombs, Human Rights Watch and other agencies say.
Libya's government says militants inspired by al-Qaeda are fighting alongside rebel forces in Misrata.
It says it is trying to protect civilians from rebels, and that doctors in the city were "trying to give a bad image of Misrata" to encourage more direct Nato intervention.
Following a wave of revolutions across the region, Libya's uprising was sparked by February's arrest of a human rights campaigner in the eastern city of Benghazi that rapidly spread to other cities.
Authorities used aircraft to attack protesters, prompting the resignation of many Libyan diplomats as rebel forces called on Col Gaddafi to relinquish his five-decade rule and open Libya up to a more democratic rule.
The EU has frozen the assets of Col Gaddafi and members of his family, and banned the supply of arms, ammunition and any equipment that could be used for "internal repression".
The European bloc plans to open an office in Benghazi to improve the flow of aid for the authorities there, EU foreign policy chief Catherine Ashton has said.