Ousted Pakistan prime minister Imran Khan suffered another jolt as the head of his economic team and one of his close aides Asad Umar resigned from all party positions, amid the government's crackdown on the opposition over the May 9 violence.

Umar, who was Khan's Pakistan Tehreek-e-Insaf (PTI) party's Secretary General, announced stepping down from all party positions shortly after he was released from Adiala Jail on Wednesday.

"Not possible for me to lead the party under these circumstances. I am resigning as Secretary General and core committee member of PTI," he said at a press conference.

Umar said he was not resigning from the party offices “under pressure”.

He, however, clarified that he has not left PTI but only resigned from the party positions.

Umar said that the most dangerous thing that happened on May 9 was that military installations were attacked.

"I think Imran Khan himself has best explained the army’s status in Pakistan. He said that we would have seen a similar fate as Syria’s if it was not for a strong army like ours. Khan sb said that my country needs my army more than me," he was quoted as saying by the Express Tribune newspaper.

His resignation came after former information minister Fawad Chaudhry on Wednesday resigned from the PTI.

Chaudhry's quitting had followed former minister for human rights Shireen Mazari's resignation. Mazari condemned the actions of the former prime minister's supporters who attacked and torched sensitive defence installations across Pakistan on May 9.

On May 9, violent protests erupted after paramilitary Rangers arrested Khan from the Islamabad High Court (IHC) premises.

His party workers vandalised a dozen military installations, including the Lahore Corps Commander's House, the Mianwali airbase and the ISI building in Faisalabad in response to Khan's arrest.

The Army headquarters (GHQ) in Rawalpindi was also stormed by the mob for the first time.

Police put the death toll in violent clashes to 10 while Khan's party claims 40 of its workers lost their lives in the firing by security personnel.

Thousands of Khan’s supporters were arrested following the violence that the powerful Army described as a “dark day” in the history of the country.

Several top PTI leaders, including Umar, Chaudary and Mazari, were arrested in the wake of the unrest.

"I feel like there should be a transparent investigation against those involved in these incidents. But thousands of PTI workers and supporters were arrested, a lot of them are innocent... it is also important that they are released as soon as possible," Umar said.

The former finance minister said that the army does not comprise just a few generals whose names are heard on TV, but thousands of soldiers who sacrifice their lives for the safety of the nation.

While Khan sees the exodus of top leaders as “forced divorces” at “gunpoint”, political experts suggest that it is an attempt to factionalise the PTI, the report said.

Prime Minister Shehbaz Sharif said on Sunday that those involved in attacks on military installations would be tried in the military courts while those charged with attacks on civilian targets would be prosecuted under civilian laws.

Pakistan's Defence Minister Khawaja Asif said on Wednesday the government was mulling a possible ban on Khan's PTI party following the attacks by his supporters on military installations after the former prime minister's arrest.

Khan was ousted from power in April last year after losing a no-confidence vote in his leadership, which he alleged was part of a US-led conspiracy targeting him because of his independent foreign policy decisions on Russia, China and Afghanistan.

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