Khan has been demanding early elections and claiming his removal from office was the result of a US-organised plot.

Khan served as prime minister for over three and half years until he was ousted by a no-confidence vote in parliament in April.
Khan served as prime minister for over three and half years until he was ousted by a no-confidence vote in parliament in April. (AFP)

Pakistan has banned ousted Prime Minister Imran Khan from holding a massive, planned rally in the capital of Islamabad.

The ban came after police detained hundreds of supporters of ousted Khan overnight ahead of a major sit-in planned by the former leader, senior party members and police sources said on Tuesday.

The government has pledged to block the protest.

According to Fawad Chaudhry, a spokesman for the Tehreek-e-Insaf party, police raids against their supporters started shortly after midnight Monday. 

READ MORE: Imran Khan's party alleges hundreds of supporters detained in police raids

Homes were still being raided on Tuesday morning and at least 400 supporters of the party were arrested across the country, Chaudhry said. 

Authorities confirmed the raids but refused to share details about any arrests.

Khan condemned the arrests on Twitter.

March on Islamabad

Khan, a cricket star turned populist politician, was kicked out of power last month in a vote of no-confidence, but has since pressured the country's fragile new coalition government by staging mass rallies across the country.

Khan has claimed his removal was the result of a US-organised plot. 

Khan plans on Wednesday to lead tens of thousands of supporters from his power base in the northwestern city of Peshawar to the capital Islamabad demanding fresh elections.

Interior Minister Rana Sanaullah warned Khan that he would “not be allowed to disrupt peace in Islamabad" and would be arrested if needed, should the rally go ahead.  

Sanaullah said the decision to ban the rally was taken after Khan’s Tehreek-e-Insaf party failed to assure the administration in writing that the rally would be peaceful.

Earlier Tuesday, authorities stepped up security in Islamabad, deploying additional officers and paramilitary Rangers. 

Large shipping containers were placed on a key road leading to the parliament building, to prevent Khan’s supporters from getting close and possibly staging a sit-in there.

READ MORE: Pakistan boosts Imran Khan's security after his claim of deadly plot

Source: AP