In The Atlantic:
In August, the FBI caught a break when it questioned a brother-in-law of KSM, Abdul Samad Din Muhammad, who had been arrested and questioned in the United Arab Emirates in November 2001 and extradited to Pakistan in 2002. Muhammad told FBI agents that Aziz Ali was in constant contact with his uncle, KSM. He also said Aziz Ali received a constant stream of Arab visitors from Pakistan at the airport and that Ali had suddenly bolted from the UAE a day or two before the Sept. 11 attacks. He didn’t have his belongings together, but insisted on leaving. When Muhammad asked Aziz Ali why he was in such a rush to leave, he didn’t get a satisfactory answer. FBI deputy legal attaché Jennifer Keenan, who was working closely on the case, was now certain that the way to get to KSM was through his nephew.
More raids initially yielded nothing, but in early September, the Pakistani police got lucky. Neighbors had pointed out that there was an awful lot of traffic through a house in the Gulshan-e-Iqbal neighborhood. Police nabbed a man leaving the house on his way to pay utility bills. Agents of the ISI investigated and detained the man, a Saudi native, who said he managed the house. His name was Mohammed Ahmad Rabbani. Rabbani’s driver proved to be quite talkative. He said Rabbani and his brother managed several similar guesthouses, all of which had a constant stream of guests. He helpfully gave police the addresses of the houses.
One of the houses was nearby, on Tariq Road. Authorities raided it and found the brother there, along with two other men, two women, and three children. They also found 20 carefully wrapped passports and almost two dozen SEGA game consoles that had been modified for use as detonators for explosives. The passports were for members of Osama bin Laden’s family. The police interrogated the children to determine if they were bin Laden’s. One of the women was a caretaker, and one child was hers. Two of the children were brothers. The other woman was a nanny to the brothers — and the man was her companion. The two boys, ages seven and nine, were named Omar and Abdullah. No, they said, their father’s name was not bin Laden; it was Khalid Sheikh Mohammed. The women were caretakers and nannies. More: