Hours after they fought the first street battles of the war in Tripoli Sunday, Libya's rebels claimed they had launched a daring mission to penetrate the capital, which until Saturday night had been considered Muammar Qaddafi's last stronghold.
An advance party "from Misrata reached Tripoli this dawn by sea and joined the Tripoli rebels," said Abdullah Melitan, a spokesman for the rebels.
If verified, the claim suggested that the rebels are preparing an offensive on the capital itself, which -- in the absence of Qaddafi's death or flight to exile -- must fall, if the rebels are to claim victory.
Gunfire, anti-aircraft fire and explosions rang out across the capital overnight as rebel commanders hailed the start of an attack on the dictator’s final stronghold.
But in a typically defiant audio message broadcast on state television early on Sunday, Qaddafi claimed to have repelled the rebels in the city.
"Those rats ... were attacked by the masses tonight and we eliminated them," he said, adding that rebel activity in Tripoli had amounted to little more than "fireworks". He called on his supporters to mass against the rebels and win back the towns that had fallen to them.
Residents reported fighting in neighbourhoods in the north, east and south-west of Tripoli on Saturday night and said rebels were in the streets, although the Libyan government insisted the capital was “safe and stable”. A British nurse working in Tripoli told the BBC that it had been a "horrific night" of fighting in the capital.
Jumma Ibrahim, a rebel spokesman, said: “The revolution from inside Tripoli has officially started in many parts ... of Tripoli, and is expected to spread to all of Tripoli.”
Colonel Fadlallah Haroun, a rebel military commander in Benghazi, claimed the fighting marked the beginning of an assault on the capital co-ordinated with NATO forces.
Col Haroun said that weapons were assembled and sent by tugboats to Tripoli on Friday night.
“The fighters in Tripoli are rising up in two places at the moment - some are in the Tajoura neighborhood and the other is near the Matiga airport,” he told the Arabic satellite channel Al-Jazeera.
A senior rebel official said the "next hours are crucial" and claimed many pro-Qaddafi units had fled.
"The zero hour has started. The rebels in Tripoli have risen up," said Abdel Hafiz Ghoga, vice-chairman of the NTC, based in the eastern Libyan city of Benghazi.
"There is co-ordination with the rebels in Tripoli. This was a pre-set plan. They've been preparing for a while. There's co-ordination with the rebels approaching from the east, west and south."
Mr Ghoga said NATO warplanes were launching raids to distract Col. Qaddafi's forces. "The next hours are crucial. Many of their (pro-Qaddafi) brigades and their commanders have fled."
A Libyan government spokesman admitted that “armed people sneaked into Tripoli” but claimed they had been dealt with. They said the rebels attacked in “small groups of a few dozen”.
But Franco Frattini, the Italian foreign minister, said: "Everything points to this tragedy coming to an end."
While the precise scale of Saturday night’s unrest was unclear, rebel advances on Tripoli in the past few days have already heaped unprecedented pressure on Qaddafi.
The six-month conflict took a dramatic turn last week when rebels suddenly seized the coastal city of Zawiyah just 30 miles west of the capital. They were reported on Sunday to be as close as 20 miles away.
“It is a victory for us if he has gone,” said Yusuf Al-Hamadi, a student, aged 23. “But I cannot believe it yet.”
But Qaddafi has vowed he will 'blow Tripoli up' if rebels enter the city and has pledged to die in Libya.
Al-Hamadi's victory hasn't come yet.