Khan's tweet came after the arrest of Salar Kakar, a PTI social media activist from Balochistan.
Police had summoned Kakar on Tuesday and asked him to submit his mobile and laptop to Federal Investigation Agency (FIA).
Kakar was accompanied by former president of the PTI's Balochistan chapter, Qasim Suri, to the police station.
Dawn quoted Suri as saying that the police told Kakar the FIA had been asking about him.
Police also asked Kakar to disclose the passwords of all his social media accounts.
Suri alleged that the FIA deputy director had received instructions from Islamabad to bring Kakar to the capital.
He said the social media activist was brought to Islamabad by road and was not even allowed to return home to fetch any belongings.
Meanwhile, the PTI has decided to raise this issue in the parliament.
The PTI lawmakers on Wednesday submitted a calling-attention notice seeking to discuss the issue of harassment of social media activists and the alleged signing of secret agreements with social media sites to block accounts of users who are critical of government policies.
Members of National Assembly Asad Umar, retired Col Amirullah Marwat, Nafeesa Inayatullah Khattak, Aquibullah and Dr Shireen Mazari submitted the notice on behalf of the PTI.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)