Muammar Gaddafi's forces launched a fresh artillery bombardment on Zawiyah on Tuesday and surrounded the town in the west of Libya, Al Jazeera reported.
It did not give further details about the attack on the town which has been a focus for heavy fighting between government forces and rebels.
Residents who had been speaking to journalists about developments have not been reachable.
Civilians were surrounded by Gaddafi forces in two western towns, Misrata and Zawiyah, and in the east warplanes hit the rebel-held oil terminal town of Ras Lanuf as strikes and counter-attacks pointed to an increasingly protracted conflict.
Two Arab papers and al Jazeera television said Gaddafi was looking for a pact allowing him to step down, but Libyan government has denied holding talks with rebels, Al Arabiya television reported. Al Arabiya did not give details or a source of its initial report. But it then quoted a Libyan Foreign Ministry spokesman as saying the accusations of the Libyan National Council, an interim body set up by rebels, did not deserve a response.
One of Gaddafi's sons, Saadi, said in an interview with Al Arabiya television his father had not yet thrown his army into full battle against the rebels, saving it to shield Libya against foreign attack and to protect "sensitive sites".
"The tribes are all armed, there are forces from the Libyan army and the eastern region is armed. The situation is not like Tunisia or Egypt," said Saadi. "If something happened to the leader, who would be in control? A civil war would start."
The battlefield in eastern Libya around important oil terminals has become mired in attack and counter-attack between the loose-knit rebel army of young volunteers and defectors and the Libyan armed forces in a buffer zone of barren landscape between the east and the west of Libya.
The largely inexperienced rebels lack the firepower of their rivals. They have no warplanes to back them up and rely mostly on heavy machineguns, anti-aircraft weapons and rocket propelled grenades. They travel by 4x4 pick-up trucks.
But their agility, often fairly chaotic at the front, has given them a degree of protection from Gaddafi's forces, who have proved more effective at quashing the rebellion in the west around the Libyan leader's Tripoli powerbase.
U.N. aid coordinator Valerie Amos said the fighting across Libya meant that more than a million people fleeing or inside the country needed humanitarian aid.
"Humanitarian organisations need urgent access now," she said. "People are injured and dying and need help immediately." The United Nations appealed for $160 million for an operation over the next months to prepare shelter, food and medicine.
Britain and France spearheaded a drive at the United Nations for a no-fly zone over Libya.
The White House pushed back against rising pressure from some U.S. lawmakers for direct intervention in Libya, saying it first wanted to figure out what military options could achieve in this oil-producing desert state which is racked by conflict.
British Foreign Secretary William Hague said London was working with its partners "on elements of a resolution on a no-fly zone, making clear the need for regional support, a clear trigger for such a resolution and an appropriate legal basis".
A French source said France also was working with its U.N. partners on a no-fly zone resolution. Gulf states called for a no-fly zone and an urgent Arab League meeting.
Western allies differ over how a no-fly zone might be implemented. The United States has said it would involve a large-scale military operation, including strikes on Libyan air defences, but some military analysts have said it could be limited to preventing flights in Libyan airspace, without a big preliminary campaign.
U.S. Defense Secretary Robert Gates, in Afghanistan, said action should be taken only with international backing. The White House said all options were on the table, including arming rebels.
Russia, a permanent member of the U.N. Security Council with veto powers, said it opposed foreign military intervention.
NATO has launched 24-hour surveillance of Libya with AWACS reconnaissance aircraft, the U.S. ambassador to NATO said.
In the rebel-held city of Misrata, the wounded were being treated on hospital floors because of a catastrophic shortage of medical facilities in the besieged city, a resident said.
Misrata is the biggest city in the west not under the control of Gaddafi, and its stand against a militia commanded by his own son has turned it into a symbol of defiance.
In the east, warplanes launched strikes on the rebel-held oil town of Ras Lanuf 600 km (400 miles) east of the capital Tripoli. One ripped through a car carrying a family.
Shipping sources said the fighting had closed the Ras Lanuf terminal and the oil port of Brega. Brent crude prices rose above $118 a barrel on Monday before falling back to $115 and U.S. prices pushed to their highest level since September 2008.
Youcef Yousfi, president of the Organisation of Petroleum Exporting Countries, said there were no plans for a crisis meeting of the group and high prices were short term.
The Libyan government says it is fighting against "al Qaeda terrorists" and maintains its security forces have targeted only armed individuals attacking state institutions and depots.
So far tens of thousands of migrant workers have fled but few Libyans.
"If we get a massive outflow of Libyans, this would create a refugee situation, so we appeal to all countries to keep their doors open and be ready to provide assistance as humanitarian law requires," U.N. High Commissioner for Refugees Antonio Guterres said.
EU foreign ministers ordered an arms embargo on S. Sudan and urged international partners to follow suit
Putin said the Ukraine crisis should be resolved as quickly as possible and that Moscow's aim was to restore political unity to Ukraine
Fatah and Hamas – the latter of which has run the Gaza Strip since 2007 – continue to accuse one another of hindering April's reconciliation deal
Comments by senior officials suggest Beijing may take harder line against territory as police launch investigation.
Bani Arshid, who has been in custody since last month, said he had initially refused to attend the session to protest the "unconstitutionality" of the military trial, saying he had been brought to the courtroom involuntarily.
Schoolchildren in India observe 2-minute silence in memory of victims of the Pakistan school after PM Modi's appeal
Sweden should stop giving automatic permanent residency to people granted asylum in the Nordic country, and cut benefits to motivate them to work, the head of the opposition Christian Democrat party said on Thursday.
Suspected Boko Haram gunmen kidnapped more than 100 women and children during a raid on the remote northeast Nigerian village
Kuwait said it accepted an Iraqi request related to reparations imposed by the U.N. Security Council over its 1990 invasion of Kuwait
As U.S. fighter jets pound ISIL targets inSyria, Washington's coalition allies appear increasingly absent from the air war.
On Tuesday, Ya'alon said that the Israeli army could be "forced" to launch another attack on the coastal enclave.
Delegates representing President Salva Kiir and rebel leader Riek Machar sat down together to hammer out a peace deal under the sponsorship of the Intergovernmental Authority on Development
A Pakistani court granted bail on Thursday to a man accused of masterminding a deadly 2008 rampage through the Indian city of Mumbai, lawyers said.
Putin breaks silence on rouble problems this week, where economic problems threaten Putin's standing and one former ally says he should work out "exit strategy"
Kenyan opposition lawmakers disrupted a vote to authorise tough terrorism-related measures that rights activists say threaten civil liberties and free speech, forcing the parliamentary speaker to postpone the session.
Franklin Drilon says Visiting Forces Agreement must be reviewed after US refuses to hand over murder suspect