At least two police officers and two protesters were killed in clashes in the eastern city of Lahore, where thousands of activists from the banned Tehreek-e-Labbaik Pakistan party gathered to demand the release of their leader.
Violent clashes have erupted between Pakistan's security forces and Islamists in the eastern city of Lahore, killing at least two policemen and two demonstrators.
The incident happened on Friday after thousands of activists launched their “long march" from the city toward the capital, Islamabad, demanding that the government release the leader of their outlawed party.
The rallygoers had set out for Islamabad to pressure the government to release Saad Rizvi, the head of the Tehreek-e-Labbiak Pakistan party.
Rizvi was arrested last year amid demonstrations against France over publishing caricatures of Islam’s Prophet Muhammad.
Pakistan has deployed police and paramilitary personnel to prevent the demonstrators from leaving Lahore. Authorities also suspended cellular service in parts of Lahore and blocked roads.
The situation worsened when police tried to stop the rallygoers, witnesses said.
The violence disrupted normal life in parts of Lahore, where residents were facing problems in reaching home because of the closure of some roads and continued clashes between police and protesters.
Rizvi's party said they were peaceful and that police suddenly started firing tear gas shells.
Sajid Saifi, a spokesman for Rizvi's party, blamed police and paramilitary forces for initiating the violence.
He said the use of force by authorities killed at least two demonstrators and injured hundreds of people. Some were having a breathing problem because of the use of tear gas, he added.
Police spokesman Rana Arif said two of the police officers were killed and another was injured when protesters threw stones.
Rizvi's supporters said several protesters were wounded when police swung batons and fired tear gas.
Shipping containers were also being brought in to block the main Islamabad highway and surrounding roads to keep protesters from entering the capital from other nearby cities, towns and villages.
The TLP has a history of staging protests and sit-ins to press their demands.
On Friday, Rizvi's party leader Ajmal Qadri said his supporters launched the “long march" after talks with the government failed to secure Rizvi's release.
Rizvi’s party gained prominence in Pakistan’s 2018 elections, campaigning on a single issue: defending the country's blasphemy law, which calls for the death penalty for anyone who insults Islam.
It also has a history of staging violent protests to pressure the government to accept its demands.
The latest development comes at a time when Prime Minister Imran Khan was visiting Lahore.