Seen as a divisive figure by most in Pakistan, Dr. Qadri, who lives in Canada, arrived in Lahore even as his supporters clashed with police.
Qadri's plane reportedly circled above Benazir Bhutto International Airport near Islamabad for an hour and a half before it was diverted to Lahore.
Qadri has been at the forefront of a campaign for greater transparency and less corruption in institutions."
Police had to fire tear gas and fought running battles with Qadri supporters outside the airport after 2,000 protesters gathered there to greet their leader.
Even after the aircraft landed in Lahore, Qadri and his supporters refused to leave the plane, demanding it fly back to Islamabad or the army send a representative to give him protection.
Outside Lahore Airport, about 700 supporters held a peaceful rally shouting "Long live Qadri".
Discontent with the government is already high due to power shortages that have crippled the economy as well as a persistent Taliban insurgency which stages attacks around the country.
Police have cordoned off major roads leading to the airport serving Islamabad with cargo containers, and blocked mobile phone services to prevent protesters from communicating with each other.
At least eight people including a policeman were killed in Lahore last week when protesters clashed with police in a standoff over Qadri.
The government, according toa report in the Dawn, has imposed Section 144 in Rawalpindi that prohibits the gathering of more than four persons at a place.
It has also blocked all routes to and from Islamabad Airport.
PAT supporters are reported to be holding protests in support of Dr. Qadri in various cities.