Pakistani police fired tear gas, baton-charged and detained supporters of ousted Prime Minister Imran Khan on Wednesday to stop them from reaching the capital Islamabad to demand fresh elections, officials and witnesses said.

Political and economic volatility has deepened in the nuclear-armed South Asian nation ahead of a likely announcement by the IMF later in the day on whether it will resume a $6 billion rescue package.

Khan, ousted in a confidence vote last month after losing his partners in his coalition, has urged supporters to march on Islamabad and stay there until the new government is dissolved and a date for a fresh election is announced.

Islamabad’s entry and exit routes have been blocked, as well as all important sites, including parliament, government offices and diplomatic missions, officials said. Entry and exit points were also blocked to and from all major cities in Punjab province and on the Grand Trunk Road (GTR), they said.