Islamabad has been placed under lockdown as the Pakistani government deploys tens of thousands of police and paramilitary forces, blocks highways, and shuts down internet access to prevent a massive protest called by jailed former Prime Minister Imran Khan.

The demonstrations come in response to Khan's call for his supporters to march on the capital, demanding his release and free elections.

Khan, leader of the Pakistan Tehreek-e-Insaf (PTI) party, has been in jail for over a year, facing numerous charges that he claims are politically motivated.

His supporters allege widespread rigging in February's elections and accuse the ruling coalition, led by Prime Minister Shehbaz Sharif, of orchestrating his imprisonment to prevent his return to power.

Massive protest march underway

A convoy of tens of thousands of PTI supporters from across Pakistan began heading toward Islamabad on Friday, with party officials estimating more than 70,000 marchers from Khyber Pakhtunkhwa alone.

The protest is expected to reach the capital by late Monday or Tuesday. PTI leaders, including Khan's wife Bushra Bibi, have vowed to continue the march until all political prisoners, including Khan, are released.

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However, the government has imposed roadblocks and deployed tear gas, rubber bullets, and stun grenades to disrupt the protest.

PTI alleges that over 5,000 protesters and leaders have been arrested, with violent clashes reported as demonstrators retaliated by throwing stones and setting police vehicles on fire.

Islamabad fortified

According to reports, Islamabad has been transformed into a fortress, with shipping containers blocking key roads and the red zone, home to government institutions, completely sealed off.

Internet access and messaging services have been restricted in Punjab, Sindh, and Khyber Pakhtunkhwa to hamper coordination among protesters.

The government has condemned the protest, with federal minister Ahsan Iqbal accusing Khan of trying to bypass the justice system through force.

"His release hinges on clearance from the courts. He will have to clear himself from the cases registered against him. Without this, the government cannot release him," Iqbal said.

Read more: US questions Pakistan election process amid Imran Khan allies lead

Political and military standoff

Khan's fall from power in 2022 followed a rift with Pakistan's powerful military, which he now accuses of engineering his legal troubles.

Observers suggest that this protest may be Khan's last attempt to pressure the military establishment into negotiations to avoid being tried in a military court. However, senior military officials have indicated no interest in striking a deal.

PTI officials claim the military requested meetings with Khan in Rawalpindi's Adiala jail to convince him to call off the march, but the party has refused to back down.

PTI information secretary Shaikh Waqas Akram told reporters that the party was "fully prepared" to reach Islamabad, no matter the obstacles ahead.