ISLAMABAD, Oct 5, 2024 (BSS/AFP) - Pakistan's capital was locked down on Saturday, swarmed by security forces with mobile internet cut as supporters of jailed ex-prime minister Imran Khan attempted to seize the streets in protest.

Khan was barred from standing in the February elections that were marred by allegations of rigging, sidelined by dozens of legal cases. 

But his Pakistan Tehreek-e-Insaf (PTI) party has defied a crackdown to needle the government with regular demonstrations.

PTI activists began driving to Islamabad on Friday from his powerbase in northwestern Khyber Pakhtunkhwa province, but were met with shipping container roadblocks and volleys of tear gas.

On Saturday, small and scattered convoys pressed in on Islamabad in defiance of the government which approved troops for deployment on the streets -- citing the need to guarantee security ahead of a Shanghai Cooperation Organisation (SCO) summit due to open on October 15.

"I am so proud of all our people," said a message from Khan posted on social media site X on Saturday afternoon. "You showed unfaltering resilience and courage as you came out yesterday and overcame unbelievable obstacles."

Protests were also due Saturday in Lahore, however the main motorway linking the eastern megacity to the capital was blocked.

Amnesty International said the communications cuts and road blockades "infringe on people's right to freedom of expression, access to information, peaceful assembly and movement".

"These restrictions are part of a worrying clampdown on the right to protest in Pakistan," the rights group said.

The social media site X -- formerly Twitter -- has also been blocked across Pakistan since after the election, when mobile internet was likewise cut on polling day and PTI allege widespread vote tampering took place.

The 72-year-old Khan served as prime minister from 2018 to 2022, when he was ousted in a parliamentary no-confidence vote after falling out with the powerful military establishment considered Pakistan's political kingmakers.

As opposition leader he led an unprecedented campaign of defiance before becoming tangled in slews of court cases he claims have been orchestrated to prevent his return to power.