Former Prime Minister Nawaz Sharif was deported to Saudi Arabia on Monday, hours after he had landed in Pakistan from seven years in exile hoping to head a campaign to replace the country's U.S.-allied military ruler.
About four hours after he arrived on a flight from London, Sharif was taken into custody and charged with corruption, but was then quickly spirited to another plane and flown to Jiddah, where he was whisked away in a convoy from the airport, witnesses said.
By deporting Sharif, President Gen. Pervez Musharraf has sidelined a powerful political enemy, but the move is likely to deepen his growing unpopularity and reinforce public perceptions that he is an authoritarian ruler ahead of presidential and legislative elections.
Musharraf's grip on power has faltered after a failed attempt to oust the country's top judge ignited mass protests, but he still plans to seek a new five-year term in office by mid-October.
His government is also struggling to combat surging Islamic extremism that has spread from the Afghan border where al-Qaida leader Osama bin Laden is believed to be hiding.
Sharif's brother, Shahbaz Sharif, who stayed behind in London, said their party would submit a petition with the Supreme Court to challenge the deportation.
"This will be counted as the blackest day in Pakistan's history," he said on Geo TV. "I do not have words to describe my grief."
The deportation is likely to stoke confrontation with opposition activists, who battled police Monday morning on roads leading to Islamabad airport that authorities had blockaded with trucks, tractors and barbed wire. None were able to get close to the airport.
Police fired tear gas and supporters threw rocks in at least two locations near Islamabad and also a bridge on main highway leading to the capital from Pakistan's northwest frontier. Several people were injured at each clash, Associated Press reporters said.
At least four other senior opposition leaders were also put under house arrest, officials said.
Interior Ministry spokesman Brig. Iqbal Cheema said they were arrested "to ensure the maintenance of public order," under a regulation that allows authorities to detain suspects for up to three months without charge.
They included the head of a powerful political alliance that supports Sharif, Qazi Hussain Ahmed; another hard-line Islamic lawmaker, Liaqat Baluch; the acting president of Sharif's party, Javed Hashmi; and party chairman Raja Zafarul Haq, party and government officials said.
The government defended the deportation, which came despite a Supreme Court ruling last month that Sharif had the right to return Pakistan, claiming it was in the "supreme interest" of the country.
"Sharif's deportation is in accordance with law and ethics," Interior Minister Aftab Khan Sherpao said, Dawn TV and other local media reported.
Monday's deportation is the latest chapter in a decades-long relationship between Sharif and Musharraf.
Sharif appointed Musharraf to the post of military chief in 1998, but his attempt to fire him a year later triggered the coup that saw Musharraf seize power. Sharif, accused of corruption and denying landing rights to a plane carrying Musharraf that was short on fuel, was jailed but later released and sent to Saudi Arabia after allegedly pledging not to return for a decade.
Saudi intelligence chief Prince Muqrin bin Abdulaziz Al Saud said Saturday in Islamabad that Sharif should respect the agreement and that Saudi Arabia was ready to take him back.
After arriving by a Pakistan International Airlines flight from London, Sharif was surrounded by black-uniformed commandos inside the plane then shifted to the airport's VIP lounge, where a senior investigator from Pakistan's anti-corruption body served an arrest warrant.
The investigator, Azhar Mahmood Qazi, said Sharif was being arrested on money-laundering and corruption charges stemming from a sugar mill business several years ago. Sharif was accused of laundering 1.2 billion rupees (US$21.2 million), he said.
Chaudhry Shujaat Hussain, president of Pakistan's ruling party, said Sharif had been given a choice of going into exile again or be arrested. He said Sharif had chosen detention. But it emerged soon after Sharif was being flown out of the country to Saudi Arabia.
That scuppered his plans to travel in a grand motorcade to his home and political base in Lahore, about 290 kilometers (180 miles) to the south of Islamabad, to kick-start his campaign against Musharraf.
"Musharraf is capable of doing anything," Sharif told reporters on the flight from London. "He could impose martial law, but if he does, he will be the first casualty because the country will not accept that, the people will not accept that and I think the rank and file of the army will not accept that."
The European Union criticized the decision to send Sharif into exile, saying the Supreme Court ruling allowing him back should be respected.
"If there is any legal case against Mr. Sharif, he should have a chance to defend himself in a Pakistan court," said EU spokeswoman Christiane Hohmann.
Sharif's return was widely seen as a challenge to Musharraf's efforts to reach a possible power-sharing deal with another exiled former premier Benazir Bhutto that would allow him to extend his rule.
Bhutto wants corruption charges against her to be dropped and for a chance to become prime minister for a third time after general elections due by mid-January 2008.
Sharif's renewed exile could clear the way for Bhutto and Musharraf to reach an agreement, but Bhutto could face growing opposition within her own party to the idea of teaming up with the military leader whose credentials as a pro-democrat will be more fragile than ever.
Wajid Hasan, Bhutto's spokesman, said the Sharif's deportation did not affect her plans to return to the country and she would announce her travel date Friday.
He said Sharif's expulsion was "typical of a government that doesn't believe in any decency or rule of law."