Supporters of Pakistan's cricket star-turned-politician have gathered in the eastern city of Lahore for the opposition's latest anti-government rally.

Police officer, Imtiaz Sarwar, says the protesters aligned with Imran Khan's Pakistan Tehrik-e-Insaf tried to block some of the city's main roads on Monday. Thousands of people later gathered in central Lahore for a rally.

Tensions have been escalating for weeks between the government of Prime Minister Nawaz Sharif and Khan's party. Khan alleges widespread vote rigging in the 2013 vote, which brought Sharif to power.

This is the third protest by Khan in two weeks. Earlier demonstrations were held in Faisalabad and Karachi.

Khan has vowed to shut down all Pakistani cities later this week with a string of demonstrations.