Pakistani authorities have placed shipping containers on key roads and highways leading to the capital and suspended cellphone service in Islamabad in an attempt to prevent supporters of imprisoned former Prime Minister Imran Khan from holding a rally seeking his release.

Authorities in Pakistan sealed off the capital, Islamabad, and blocked cellphone services on Friday to prevent an anti-government rally by supporters of jailed former Prime Minister Imran Khan, officials said.

Police in Pakistan fire tear gas at supportersof jailed former prime minister Imran Khan:::: Islamabad, Pakistan:: Khan's supporters were holding an anti-government rally in defiance of a ban on congregating in IslamabadAuthorities had sealed off Islamabad,

The 72-year-old former cricketer-turned-politician Khan refused to postpone the protest despite calls by the government.

Authorities had cordoned off Islamabad and blocked mobile phone services to prevent the assembly, as the city remained on high alert ahead of a series of high-level diplomatic events, including the SCO summit.

Former Pakistan Prime Minister Imran Khan’s two sisters, Aleema Khan and Uzma Khan, reached Islamabad's D Chowk for a "peaceful protest" and were arrested by police.

Pakistan authorities have sealed off Islamabad and suspended cellphone services to prevent protests by supporters of jailed former PM Khan.

Pakistan Tehreek-e-Insaf (PTI) said on Friday that police arrested former Pakistan Prime Minister Imran Khan’s sisters – Aleema Khan and Uzma Khan, from D Chowk in Islamabad “for exercising her right of peaceful protest.

Police in Pakistan's capital fired teargas on Friday as they clashed with supporters of jailed former prime minister Imran Khan who were holding an anti-government rally in defiance of a ban on congregating in the city.