Thousands of marchers led by influential Islamic cleric Muhammad Tahir-ul-Qadri have arrived in the Pakistani capital from Lahore to protest government corruption and demand election reforms.
Qadri's proclaimed "Caravan of Democracy March" reached Islamabad late on January 14, more than a day after setting out for the roughly 300-kilometer journey.
Speaking later to supporters, Qadri issued an ultimatum to the government to step down within hours or face the consequences.
Supporters of the Sufi cleric have removed barriers and moved towards the parliament building, away from an officially sanctioned demonstration area, as Qadri urged them to do.
The cleric had said he hoped to attract 100,000 or more protesters to the event's ultimate destination, a site called the Blue Area that lies some 3 kilometers from the parliament building in Islamabad.
RFE/RL estimated the number of people entering the city at well above 10,000 based on correspondent and eyewitness accounts, while Pakistani Interior Minister Rehman Malik told the station that "only a few thousand" had arrived in the capital and organizers claimed there were more than 20,000 demonstrators on hand.
Eyewitnesses reported tens of thousands of marchers.
Qadri, speaking on January 13 in an interview with Reuters, called for sweeping electoral reforms ahead of national elections this spring.
"So we don't want lawbreakers to become our lawmakers."
"So [the government] wants to go to the electoral process in the same way as it [has been] for the last 60 years, so that the fake degree holders, and tax evaders, and the corrupt people, and the criminal people -- because of their special skills of maneuvering the elections -- may come back to the parliament," Qadri said.
Qadri told Pakistani media last week he was seeking to bring peace and security to the country by fighting against "terrorism, radicalism, extremism, and corruption."
He has pledged that he and his followers will remain in Islamabad until their demands are met, with many marchers bringing with them food, blankets, and tents.
There was a large police presence throughout Islamabad and along the route of the march.
Interior Ministry spokesman Nawazish Ali said there was no restriction on the marchers entering Islamabad but added that "strict action" would be taken against anyone who breaks the law.
Ali said there was a contingency plan ready in case any unrest erupted but he did not elaborate.
Mobile-phone service was switched off in some areas of Islamabad and along the route of the march due to warnings from Interior Minister Malik that militants might try to attack the march.
Authorities left open the Blue Area of the city in anticipation of the demonstrators' arrival. Several hundred people had reportedly gathered there ahead of the expected arrival of the marchers.
Islamabad has accused Qadri, who returned to Pakistan last month after years in Canada, of trying to derail elections. Qadri has denied the allegations.
With reporting by AFP