Demonstrators have blocked a major highway, paralysing Islamabad for weeks. According to a Geo TV report, the daily cost of deploying forces to contain the protest stands at 5 million Pakistani rupees.
On Saturday, a notification issued by the Ministry of Interior had said a sufficient number of troops, to be determined by the Commander of the 111 Brigade, were being deployed in the capital to assist civil authorities in maintaining law and order. Numerous supporters are from ultra-conservative Tehreek-e-Labaik party, who accuse Law Minister Zahid Hamid of blasphemy.
The police operation and reaction from protesters, who had camped out for the last 20 days, sent scores to hospital with wounds caused by stoning and respiratory problems from tear gas. He said none of the police carried firearms to avoid loss of life, instead using tear gas and a water cannon to disperse the protesters, although witnesses said a police van came under attack and was set on fire after two police officers aimed assault rifles at protesters.
Late on Saturday, several smaller protests had developed in Karachi, Pakistan's largest city, as well as in Lahore, Gujranwala and Faisalabad.
The federal government has summoned the troops exercising its authority under Article 245 of the Constitution that reads: "The Armed Forces shall, under the directions of the Federal Government, defend Pakistan against external aggression or threat of war, and, subject to law, act in aid of civil power when called upon to do so".
Prime Minister Shahid Khaqan Abbasi chaired a consultative meeting on the Faizabad operation, which was attended by Gen Bajwa, director general of Interservices Intelligence Naveed Mukhtar, Punjab chief minister Shehbaz Sharif and interior minister Ahsan Iqbal.
"There have been several fatalities and scores of people have been injured in clashes between the protesters and security forces in Islamabad on Saturday".
Later in the day, security forces appeared to face difficulty clearing the crucial intersection as more and more supporters joined protesters at the site.
Protesters said four of their activists were killed, but police said there were no deaths, Reuters reports.
The operation launched by the police of the two cities and personnel of the Frontier Constabulary ended in a disappointing failure amid violent clashes between law enforcers and protesters. They reported that police arrested about 150 protesters, some with knives and pistols. In the ensuing clashes, at least six people have died, 200 have been injured and the government has called in for reinforcements from the army.
The protesters were blocking a key highway to the capital.
"The TLY, who mostly consist of Barelvi Muslims - a Sunni sect with elements of Sharia and Sufism - were until recently considered a sect that largely believed in mysticism with no inclination for politics".