Thousands of demonstrators from a banned Pakistani Islamist group clashed with police on Wednesday, killing and wounding several people from both sides, police and the group said. The clash broke out at a rally of the banned Tehrik-e-Labaik Pakistan (TLP) on a highway in Sheikhupura district just outside the eastern city of Lahore, a spokesman for the Punjab police said on Wednesday.

“TLP activists used SMG, AK 47 and pistols to target police officials as the result of which several officials were martyred,” the spokesman said. He said there were no details of the number killed but there were around 25 wounded. The group said several of their activists had also been killed or wounded. Information Minister Fawad Chaudhry said the government will use force to block the Islamists from entering the capital Islamabad. “It can’t be tolerated anymore,” Chaudhry told a news conference in Islamabad.

“We have shown restraint so far but the challenge to the state’s authority can’t be tolerated any more,” he said. Thousands of TLP activists have blocked Pakistan’s busiest highway since Friday, demanding the release of their leader and the expulsion of France’s ambassador over the publication by a satirical magazine of cartoons depicting the Prophet Mohammad. After negotiations with the government failed, the demonstrators began marching towards the capital Islamabad on Wednesday.

Life remained suspended in districts along the Grand Trunk Road where the Islamists were marching toward the capital, where the city administration has already placed shipping containers to block entry and exit routes to block the the Islamists. Police said they had tried to block the march, which triggered the clashes. The highway sit-in followed clashes in the eastern city of Lahore on Friday that killed three police.

This is the group’s third countrywide protest campaign since 2017 over a series of caricatures of the Prophet Mohammad published in the French satirical magazine Charlie Hebdo. Such caricatures are considered deeply insulting by Muslims. Charlie Hebdo first published the cartoons in 2006 and republished them last year to mark the opening of a trial over a deadly attack on the magazine by Islamist militants in 2015.