Former Pakistani prime minister Nawaz Sharif was arrested and deported to Saudi Arabia on Monday within hours of arriving home from exile, vowing to end the rule of President Pervez Musharraf.
Sharif's return from seven years in exile, most recently in London, was always 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.
He has been deported ... he has been sent to Jeddah, said a security official who declined to be identified.
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 on board the aircraft he arrived on.
Shortly before his arrest, Sharif told Reuters 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.
Five people were wounded in an exchange of fire when Sharif's supporters tried to force their way through police lines on a bridge on the road to Peshawar, a witness said.
Police fired teargas and used batons to disperse about 700 Sharif supporters and lawyers about 3 km (2 miles) away from the airport.
The protesters, waving party flags and holding portraits of Sharif, threw stones at police and chanted Go Musharraf go. Scores of supporters scuffled with police in Islamabad.
Sharif's British lawyer, Amjad Malik, who accompanied Sharif from London appealed for calm: People in Pakistan should be calm and composed and understand what has happened to their former prime minister.
Sharif was dogged by accusations of 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.
Before his arrival, authorities had detained about 4,000 Sharif supporters and several leaders of his Pakistan Muslim League (Nawaz), including the chairman, as well as three leaders of an allied religious alliance, party officials said.
Police said 250 troublemakers had been picked up.
Musharraf sent Sharif to Saudi Arabia in 2000 under what the government says was an agreement that he stay in exile for 10 years. In return, he avoided a life sentence on hijacking and corruption charges.
The government said by returning he was breaking his word at a time when Pakistan needed stability in the run-up to elections.
His return posed a major challenge for Musharraf, who has lost support since trying to dismiss the country's top judge in March.
Musharraf is preparing to seek another term in a presidential election in the national and provincial assemblies some time between September 15 and October 15.
A general election is due around the end of the year.
Musharraf is negotiating a power-sharing deal with another former prime minister in exile, Benazir Bhutto, who has come in for criticism from some in her party, Sharif and the public for negotiating with the unpopular general.
(Additional reporting by Kamran Haider and Zeeshan Haider)