Tens of thousands of anti-government protesters who have flooded into Pakistan’s capital Islamabad say they will not leave until Prime Minister Nawaz Sharif resigns.
Although protest organisers said they were determined but peaceful, the police geared up anyway.
Riot squads blocked two streets in the centre of Islamabad with shipping containers and barbed wire.
Leading the so-called ‘Revolution March’ is populist cleric Tahir ul-Qadri.
He has accused the civilian government – which has been in power for 15 months – of corruption and wants it replaced with a technocrat administration.
“The prime minister and chief minister of Punjab should immediately resign and they should be sent to jail,” Qadri told his supporters.
Another smaller protest was organised by opposition politician and former cricket star Imran Khan.
He also wants the prime minister to step down claiming that vote rigging at last year’s elections robbed his party of many seats in parliament.
Sharif won by a landslide, taking 190 out of 342 seats. Khan also did well in the elections, coming from political obscurity to take 34 seats, the third largest bloc in the legislature. But he says he should have had many more.
Those out on the streets also blamed the government for Pakistan’s high unemployment, spiralling crime and frequent power shortages.
The unrest raises questions about Pakistan’s stability at a time when the government is waging an offensive against Pakistani Taliban militants and as the influence of anti-Western and sectarian groups is growing.