TRIPOLI // "Hi, how, are you? How is your family? God bless you. Shall we get together on August 20?"
With this seemingly innocuous invitation, rebels opposed to Col Muammar Qaddafi escaped the attention of regime apparatchiks monitoring telephone calls and set the date among their supporters for the battle for Tripoli.
And indeed right on schedule, hundreds of men in the eastern districts of the capital rose up in arms last Saturday night after breaking their Ramadan fast.
At the same time, rebel forces rushed on Tripoli from their redoubts west of the city.
Together, they sought to challenge what many thought was Col Qaddafi's unshakeable grip the capital.
A week later, that grip is essentially broken. The rebels control most of Tripoli and have taken the first steps to establish a national government there, even as they pursue Col Qaddafi, who in a week has gone from supposed ruler-for-life to fugitive.
The insurgents appeared only one month earlier to be a fractured force, poised for an internal power struggle following the mysterious assassination of Gen Abdel Fattah Younis, their top military man. That perception of confusion and disorganisation was misleading, said Abdullah Belhaj, a rebel.
In fact, he said, preparations for a drive on the capital were already well under way.
In Fashloom, a secret committee to coordinate activities with the rebel leadership headquartered in the eastern city of Benghazi was formed in July. The Tripoli suburb was one of the first areas in the capital that rose up in response to the August 20 "invitation."
The group started obtaining weapons at the beginning of August, Mr Belhaj said on Thursday at a checkpoint in Fashloom, adding: "We bought most of them from Qaddafi's soldiers, who were selling them just for money."
In Zawiyat Dahmani, a seaside Tripoli neighbourhood, weapons training for opponents of the regime began in April, and cash to buy the arms came from local businessmen, said Ahmed Lajayli, 32.
Besides illegally purchased guns and underground cells, rebels and their sympathisers in Tripoli relied on another, equally subversive tool to organise their rebellion against Col Qaddafi: espionage.
By day, Mahmoud Ben Jumaa worked as senior officer in Col Qaddafi's personal security service, issuing orders to arrest or conduct surveillance on suspected rebels. At night, he was a member of the Fashloom cell, meeting secretly with regime opponents to pass on information and helping organise a citywide system of 20 secret councils to move against the regime.
Seated in what was until this week the regime's intelligence headquarters disguised as an English-language school, Mr Ben Jumaa described how the Fashloom cell met at night or at dawn when Col Qaddafi's loyalists were asleep. He and other members of the anti-Qaddafi underground both inside and outside Tripoli communicated by satellite phone. Col Qaddafi ordered the internet shut down in March and the cell phone network was heavily monitored.
Although he led a double-life, his sympathies were never divided, Mr Ben Jumaa said. "I have always been with the revolution," he insisted, blaming a coercive educational system and mandatory military service for forcing him to work for Libya's Internal Security for 20 years and helping buttress a regime he despised.
As the pressure increased on Col Qaddafi from Nato bombings and rebel forces in the east and west of the country, so did suspicion and paranoia.
Mr Ben Jumaa said he was tipped off at the beginning of August that his name was on an arrest list. He and his family immediately fled their flat for a safe house. Five hours later, government security forces his apartment building and broke down the door.
By then, planning for the Tripoli rebellion was well advanced. "Zero hour" was set in mid-August as Zawiyah, the last city on the way to Tripoli from the western mountains of Libya, was falling to the rebels. The date of August 20 seemed full of good omens, the rebels said, because it coincided with the 20th day of Ramadan, when Prophet Mohammed conquered Mecca in the seventh century.
The signal to start the uprising came thanks to Al Jazeera and Libya Al Ahrar, the rebel satellite television station. According to Mr Ben Jumaa, it was decided that as soon as Mustafa Abdel Jalil, head of the rebel Transitional National Council, uttered the last word of a speech that was broadcast on the two stations, the uprising would start.
"The end is very near" for Col Qaddafi, Mr Jalil said in the speech. "And it will be catastrophic."
Within minutes, the battle for Tripoli had begun.