Pakistan's top judge on Tuesday ordered the arrest of Prime Minister Raja Pervez Ashraf on corruption allegations, threatening to exacerbate political turmoil as thousands of protesters demanded the dissolution of Parliament.

Chief Justice Iftikhar Muhammad Chaudhry ordered the arrest of 16 people accused in graft allegations over power-generation projects in 2010 and told them to appear in court on Thursday, said a lawyer for the national corruption watchdog.

The Supreme Court order came as thousands of people, led by cleric Tahir-ul Qadri, demonstrated close to Parliament on the third day of a mass protest march, demanding the immediate dissolution of the government.