Hashmi refused to join the march towards the prime minister's house, saying it was against the collective party decision and would result in bloodshed.
"The decision to march to parliament was taken by Khan himself in violation of party decision," he said.
"This kind of behaviour is not seen in any country in the world, where people pick up sticks and protest outside the PM House," Hashmi said, adding Khan's decisions would lead to imposition of martial law in the country.
Khan hit back by expelling Hashmi from the party.
The expelled PTI lawmakers include Gulzar Khan from Peshawar, Nasir Khan Khattak from Karak, Mussarat Ahmedzed from Swat.
The internal problems have surfaced at a critical time when PTI is going through its biggest challenge.
The party wants to remove Sharif and its workers are engaged in running battles with police in the heart of capital Islamabad.
Image: Imran Khan addresses supporters in front of the Parliament house building during what has been dubbed a 'freedom march' in Islamabad. Photograph: Reuters
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