Islamabad: Pakistan Tehreek-e-Insaf chairman Imran Khan on Tuesday demanded Intelligence Bureau chief resign immediately for visiting former prime minister Nawaz Sharif in London.

The PTI chairman levelled serious allegations against the IB chief Aftab Sultan in a series of tweets, seeking explanation for Aftab Sultan’s visit at “taxpayer expense”.

“IB head must resign immediately. What was he doing visiting a disqualified PM in London over 4 days at taxpayer expense?” he said.

Taking exception to the IB’s alleged role in politics, the former cricket hero accused the civilian intelligence service of abetting Nawaz Sharif “by creating grounds for blackmailing his MNAs [Members of National Assembly] into falling in line.”

“This is how state institutions are destroyed by a mafia breaking all laws and democratic norms,” he said in a tweet.

Imran Khan said: “The official protocol given to a disgraced, disqualified PM, also accused of tax evasion, forgery, money laundering etc, is shameful. [It] Sends wrong message to society: that the powerful can break laws with impunity. Clearly this is mafia rule not democracy.”