He was blamed for going to spark a confrontation with General Musharraf, the army chief who ousted Sharif in 1999 and cast him into exile in Saudi Arabia the following year.

Sharif was arrested after a melee in an airport lounge where he and his supporters were taken after a tense 90-minute standoff with authorities back on board the aircraft he arrived on.

Shortly before his arrest, Sharif said he was happy to be home: "It's a great feeling. Up to here it's fine but beyond, through there, I don't know," he said in the airport lounge, pointing to the exit.

Earlier, security forces sealed off Islamabad airport to stop Sharif's supporters approaching. Authorities also blocked the main road to the northwestern city of Peshawar.

Sharif had been charged with corruption during his two terms as prime minister in the 1990s. An anti-corruption court last month reopened three cases against him at the request of the government.

The Supreme Court said last month Sharif had the right to return and the government should not try to stop him.