Pakistan’s anti-graft agency arrested the parliamentary leader of the Opposition on corruption charges on Monday after a court rejected a plea for bail, a move his party says is linked to planned Opposition protests against Prime Minister Imran Khan.

Shehbaz Sharif, a former chief minister of Punjab province and younger brother of former Prime Minister Nawaz Sharif, was arrested outside the Lahore court, his lawyer, Azam Nazir Tarar, said.

The charges are linked to alleged money laundering to buy properties abroad, Tarar said.

“I am disappointed,” Tarar told Reuters, adding that the arrest was a reaction to the Opposition’s threat of nationwide protests calling for Khan to step down. But information minister Shibli Faraz said courts were free to make their own decisions.

Sharif is one of several Opposition leaders facing corruption charges and arrested by the anti-graft body, often before a case is registered.