The interior ministry on Saturday afternoon issued a notification regarding the deployment of Pakistan Army in the federal capital after fierce clashes between security forces and Tehreek activists turned violent.
In most parts of the world, during protests, security forces use teargas shells to disperse the crowds.
Clashes immediately broke out between members of Tehreek-e-Labaik, a hard-line Islamist party, and some 4,000 police sent to break up the protest camp, police official Saood Tirmizi told Reuters.
Earlier, the Islamabad police, with the help of Frontier Constabulary personnel and other law enforcement agencies, launched an operation against protesters after the last of a long series of deadlines lapsed on Saturday morning without response from the agitators. "TV channels are advised to exhibit utmost sensitivity regarding the matter and refrain from live coverage", it added. The minister, however, is in Islamabad.
The protesters want the resignation of law minister Zahid Hamid for altering the declaration of lawmakers with regard to Finality of the Prophethood - a change which the government has already reversed.
The security forces could not arrest the sit-in leadership including Khadim Hussain Rizvi till now. Protesters, some wearing gas masks, fought back in scattered battles across empty highways and surrounding neighbourhoods. Helicopters and drones are being used by the authorities for aerial surveillance.
According to reports, police vehicles were targeted in the attack.
In Lahore, protesters gathered in more than 30 locations, said Kiran Nazish, a local journalist. Traffic jam has choked arteries near Data Darbar. "The government is also taking measures to ease the movement of the residents of the twin cities", he said while talking to media in Islamabad.
The Pakistani government has blocked social media such as Facebook, Twitter, and YouTube amid the ongoing operation against protesters. "Suggested to handle Islamabad Dharna peacefully avoiding violence from both sides as it is not in national interest and cohesion", Major General Asif Ghafoor, the director general of Inter-Services Public Relations (ISPR), said in a tweet referring to the conversation between General Qamar Javed Bajwa and Pakistani Prime Minister Shahid Khaqan Abbasi.