The UN Security Council and the Arab League are due to meet today to discuss the bloody uprising in Libya which rights groups say has cost hundreds of lives.
Several districts of Tripoli which saw fierce fighting yesterday are calm today, including Tajoura.
Libya's state telecoms company said disruptions had been caused by a surge of "pressure" on the networks, but Internet connections returned to normal and mobile phone lines were accessible again.
Libyan leader Muammar Gaddafi, 68, made a brief appearance on state television last night to scotch "malicious rumours" that he had abandoned the oil-rich North African nation he has ruled for more than four decades.
"Were it not for the rain, I would have addressed the young people at Green Square and spent the night with them to prove I am still in Tripoli and not in Venezuela," said Libya's strongman.
The television said it was a live broadcast from outside his home.
"It's just to prove that I am in Tripoli and not in Venezuela and to deny television reports, those dogs," Gaddafi said as he stood under a silver umbrella while about to step into a car.
Rain lashed Tripoli on Monday evening.
State media denied claims of massacres in and around Tripoli and other areas.
"They say there are massacres in several cities, towns and neighbourhoods of Libya. We must fight against these rumours and lies," wrote Al-Jamahiriya Two state television on a red ticker.
This information "aims to destroy your morale, your stability and your riches," it added.
Witnesses in Tripoli had reported "massacres" in certain neighbourhoods after the state channel announced security forces were assaulting "dens of terrorists."
But Gaddafi's son, Seif al-Islam, quoted on Libyan television, denied reports that the armed forces had bombarded the cities of Tripoli and Benghazi to the east, after Al-Jazeera television reported air raids in the capital.
With foreign countries drawing up evacuation plans, a security source in neighbouring Egypt said the military was beefing up its deployment on the Libyan border in the face of expected heavy influx of refugees.
Gunfire rattled overnight in Tripoli, where protesters attacked police stations and the offices of the state broadcaster, and set government buildings ablaze, witnesses told satellite news channels and human rights groups.
Rights groups say the government's crackdown has killed between 200 and 400.
More than 1,000 Chinese construction workers in Libya were forced to flee after gun-wielding robbers stormed their compound, stealing computers and luggage, their employer and state media in Beijing said.
UN chief Ban Ki-moon said he spoke personally with Gaddafi by telephone for 40 minutes yesterday and "forcefully urged him to stop the violence against demonstrators," a UN spokesman said.
Libya diplomats from the United Nations to Australia either resigned in anger -- including Tripoli's ambassador to India, Ali al-Essawi, a former trade minister -- or openly protested.
"My resignation is because of the massive violence against civilians in my country," Essawi told AFP by telephone. "Yesterday they started to use airplanes to bomb civilians demonstrating peacefully. This is unacceptable."
Two Libyan fighter pilots -- both colonels -- flew their Mirage F1 jets to Malta and said they had defected after being ordered to attack protesters in Benghazi, Maltese military sources told AFP.
Libya's justice minister, Mustapha Abdeljalil, had also reportedly resigned in protest at "the excessive use of force."
Benghazi, Libya's second city and an opposition stronghold in the east, has fallen to anti-regime demonstrators after military units deserted, the Paris-based International Federation for Human Rights reported.
It said protesters also controlled Sirte, Tobruk in the east, as well as Misrata, Khoms, Tarhounah, Zenten, Al-Zawiya and Zouara, closer to the capital.