Supporters of Canada-based cleric Tahir-ul-Qadri march towards Parliament as they take part in an anti-government demonstration in Islamabad on August 19

PM just told me he has ordered the police not to use any kind of force against the protestors as women & children are in the front rows. - Maryam Nawaz Sharif (@MaryamNSharif) August 19, 2014

Tens of thousands of protesters led by ex-cricketer-turned politician Imran Khan and a populist cleric marched on Pakistan's Parliament on Wednesday in a bid to depose the prime minister, bringing a week-long political drama to a head. ( See Pics Khan, the former cricket star who leads the Pakistan Tehreek-e-Insaaf (PTI) party, and preacher Tahir-ul-Qadri say last year's general election was rigged and have demanded that Prime Minister Nawaz Sharif should resign. ( Buzz on Twitter Their five-day protest rally in Islamabad, and the two-day "long marches" from the eastern city of Lahore that preceded it, have piled pressure on the government little more than a year since its landslide victory.The government had ordered them not to enter the capital's "red zone", which houses key buildings including Parliament, the prime minister's house and numerous Western embassies.But Khan and Qadri defied the call and soon after midnight on Wednesday thousands of their supporters entered the high-security red zone, using cranes to remove shipping containers put in place to seal the area.Tens of thousands of security personnel have been deployed to maintain order and on Tuesday evening the government doubled the contingent of soldiers guarding sensitive buildings in the red zone to 700.Despite fears of violence, there were no major clashes as the protesters entered the red zone, and the government pledged restraint."We will avoid use of force, human lives are much more precious for us, they have brought innocent children and women," said information minister Pervez Rashid.Both Khan and Qadri have ordered their followers, who number an estimated 35,000, to avoid violence as they stage sit-in protests outside Parliament."We will protest in front of the Parliament, we will not enter inside but will stage such a big crowd that people will forget Tahrir Square," Khan told cheering followers.He said if Sharif did not resign by Wednesday evening, he would lead his supporters to the prime minister's official residence.The decision to beef up the troop deployment was taken at a meeting chaired by Sharif and attended by army chief General Raheel Sharif.Nuclear-armed Pakistan has experienced three military coups and the protests triggered speculation about possible intervention by the armed forces.Sharif's Pakistan Muslim League-N (PML-N) party has accused the protesters of trying to derail the nation's perennially fragile democratic system as the government struggles with Taliban militancy and a flagging economy.Opposition parties have shunned Khan's call to unseat the government, while newspapers and business leaders have also criticised Khan's tactics, which include a call for "civil disobedience".Britain, one of Pakistan's leading partners and a major aid donor, urged the two sides to find a democratic solution to the crisis."We strongly support a democratic Pakistan and the use of democratic institutions to resolve political disputes," British foreign minister Philip Hammond said in a statement."I hope that all parties in Pakistan can work together under the Constitution to peacefully resolve current political differences."The European Union also voiced its support for democracy in Pakistan -- and linked it to a highly prized trade deal.PTI on Monday dramatically announced it would resign all 34 of its seats in the 342-member parliament and three out of four provincial assemblies.Planning and development minister Ahsan Iqbal on Tuesday said the protesters had no mandate for their proposed "revolution"."You have a few thousand crazy guys but 180 million people who have elected this government are guarantors of this government," Iqbal told reporters.Last week Sharif tried to head off the protests by setting up a judicial commission to investigate rigging allegations, but Khan dismissed the proposal immediately.The government has also set up a parliamentary committee to look at electoral reform.At a joint press conference of all opposition parties except PTI, Khurshid Shah, a senior figure in the Pakistan People's Party (PPP) urged Khan to come to the negotiating table.

The general election of May 2013 which swept Sharif's Pakistan Muslim League-N (PML-N) party to power - and brought PTI its best-ever result - was rated as free and credible by international observers but both Khan and Qadri insist it was fixed.