How did Abdul Aziz escape the Red Mosque madrasa in Malala Yousafzai's memoir, I am Malala?

In chapter 10, Malala describes how the Red Mosque madrasa was surrounded by “tanks and armored personnel carriers.” The mosque, being in Islamabad, run by Abdul Aziz and his brother, Abdul Rashid, had become an increasingly dangerous source of terrorism. As well as spreading propaganda on behalf of Osama bin Laden, it also trained its girls to become suicide bombers and encouraged them to raid houses. It also set up its own courts to dispense the Islamic justice which it said the state failed to enforce.
On the night of July 3, 2007, the Musharraf government decided to take action and sent in commandos to surround the mosque, as noted above. The commandos “cut off the electricity in the area” and “blasted holes in the wall surrounding the mosque.” With helicopter gunships hovering overhead, they called for the girls inside the mosque to surrender. When some of the girls eventually emerged from the mosque the following evening, Abdul Aziz hid himself among them, “disguised in a burqa, along with his daughter.”