Libya crisis: Rebels seek to break out of Misrata
At least 14 Libyan rebels have been killed during an attempt to break out of their western enclave of Misrata.
Pro-Gaddafi forces are reported to have killed the rebels who had surged towards the south, east, and west.
Misrata suffered intense bombardment until mid-May, when pro-Gaddafi forces were driven away by rebels.
The latest fighting comes as Nato intensifies its campaign in Libya, calling for the international community to prepare for a post-Gaddafi era.
Earlier a rebel spokesman had told Reuters news agency there had been a fresh government offensive on Misrata.
On Wednesday explosions could be heard to the east of the city as government forces responded with Grad rockets to the rebel offensive.
Rebel fighters told the BBC's David Loyn in Misrata that they had moved several miles forward of their eastern frontline to the outskirts of the next coastal town, Tawargha.
Twelve rebels are said to have been killed in the east and two in the west. Doctors say 24 people were wounded.
Field ambulances took a stream of casualties for treatment, and traffic built up around Misrata hospital as people responded to an appeal for blood donors, our correspondent adds.
He says the main commander on the southern front, Salahuddin Badi, was one of those wounded. He was seen making an inspirational speech to his men, with blood streaming down his face, before going off for medical treatment.
The government has so far not commented on the latest violence.
Meanwhile, Nato ministers met in Brussels on Wednesday to discuss the alliance's nine-week campaign. Afterwards, Secretary General Anders Fogh Rasmussen told reporters that "real progress" had been made.
Nato action, he said, had "prevented a massacre" in Benghazi in the east - the rebels' stronghold - and in Misrata.
Mr Rasmussen urged the UN and other bodies to work to "ensure a smooth transition" to democratic, post-Gaddafi Libya. "The time to start planning is now," he said.
Last week Nato extended its air operations over Libya for another 90 days, as it increased the scope of its UN-mandated campaign to protect civilians.
Since then, British and French attack helicopters have gone into action and command centres in Tripoli have been pounded.
On Tuesday Nato carried out its heaviest daytime raids of its campaign on what it said were command and control centres in and around the capital, with more than 20 air strikes by low-flying jets.
In an address broadcast on state TV on Tuesday Col Muammar Gaddafi vowed to remain in the country "dead or alive", and said Libyans would soon defeat their enemies.
"The Libyan people will march, in the direction of the east or the west, or to any place where there are armed gangs to strip them of their arms without fighting," Col Gaddafi said.
Addressing Nato, he added: "Your planes will not be able to stop these marches of the millions, nor will the armed gangs that you support be able to resist for even a minute."