His arrival in Islamabad was met with raucous cheers, and supporters showered his black SUV with rose petals.
Qadri also asked his supporters to take the security of the capital in their hands and guard and protect each of the buildings of Islamabad. The cleric took an oath in front of the crowd that they all will remain peaceful but stay in Islamabad until the revolution is completed.
"They are no more rulers but former rulers. Don't follow their orders! I have come here to get you out of their slavery," he said.
Many of the protesters had blankets and appeared ready to camp.
Some of Qadri's comments have sparked concern that the cleric is being uses as a front for the Pakistani military to disrupt the democratic process just as the country prepares for a historic transfer of power from one civilian government to another.
He has called for a military role in picking the caretaker government that will take over temporarily ahead of elections and has said it could stay in place longer than normal to enact necessary reforms.
Those comments, as well as questions about the origins of his funding, have sparked fears Qadri is really trying to derail the upcoming vote on behalf of the military, which is believed to dislike both the main political parties vying for power, and pave the way for a military-backed caretaker to hold power indefinitely. Qadri has denied any such involvement.
Associated Press writers Rebecca Santana and Sebastian Abbot in Islamabad contributed to this report.
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