ISLAMABAD, PAKISTAN — Men armed with assault rifles battled for hours Saturday in a confrontation between pro- and anti-government forces that raged through residential neighborhoods in Karachi, the country's largest city, killing at least 28 people and injuring more than 100 others.
The strife in the volatile port city of 15 million people, which has a long history of political violence, was the worst yet during a crisis that erupted two months ago when President Pervez Musharraf suspended the country's top judge.
Backers of Musharraf appeared to be the driving force behind the violence in Karachi.
Pakistan is an important American ally in the fight against Al Qaeda and the Taliban, both of which have been using the wild frontier between Afghanistan and Pakistan as a base for planning attacks against Western targets, including the NATO-led force in Afghanistan.
In a Karachi neighborhood close to the international airport, smoke billowed from burning barricades, panicky motorists abandoned their vehicles, and residents of high-rise apartment buildings rushed for cover in inner rooms as the chaotic fighting continued through much of the day.
Musharraf, speaking at a rally in the capital, Islamabad, appealed for calm, but stopped short of declaring martial law in Karachi.
"If you are unhappy about what has happened ... halt these protests," the president, who took power in a bloodless coup in 1999, told nearly 50,000 supporters in the capital. "There is no need for an emergency -- the people are with me."
The political confrontation began March 9, when Musharraf suspended the country's most senior jurist, Iftikhar Mohammed Chaudhry, accusing him of misconduct. But many believed the president was seeking to push aside the Supreme Court chief justice to preclude a challenge to the validity of elections to be held this year.
A judicial panel is examining Chaudhry's suspension, but it could take months to reach a conclusion.
The fighting between pro- and anti-government forces broke out just before Chaudhry was to address a large gathering of lawyers, who have rallied to his cause. He was expected to call for his reinstatement, and to urge Musharraf to either step down or give up his military role -- a stance that his backers believe was the reason he was suspended from his post.
On arrival, though, Chaudhry was unable to leave Karachi's international airport because of the violence. By evening, with fighting still raging in nearby neighborhoods, he flew back to the capital.
Opposition parties said the violence was orchestrated by the pro-government Muttahida Quami Movement, or MQM, which controls the municipality. Leaders of the opposition, who had planned to greet Chaudhry at the airport, said police stood idly by as they were beaten and intimidated at the airport, and during violence that subsequently spilled over into large areas of the sprawling city.
The offices of one private Pakistani network in Karachi, Aaj Television, were sprayed with gunfire while vehicles burned outside, its staff said. However, the station stayed on the air.
Near the airport, pro-government forces made makeshift barricades of shipping containers and flaming vehicles, witnesses said.
In Pakistan, both a presidential vote and parliamentary elections are to take place this year. Opponents of Musharraf have accused him of engineering the parliamentary elections in a way that will ensure his continuing grip on power.
The current crisis is the most serious of Musharraf's tenure.
The violence threatened to put a damper on the Pakistani leader's recent reported overtures to former Prime Minister Benazir Bhutto, now in exile. News reports have said Bhutto is willing to give Musharraf political support in exchange for some undefined role in government and the dropping of corruption charges against her.
Backers of Bhutto's Pakistan People's Party were among those clashing with pro-government supporters in Karachi. The fighting continued after night had fallen.
Chaudhry's supporters denounced the government for failing to provide adequate security for him.
"This is a message that the chief justice should refrain from challenging the military ruler," said retired Justice Tariq Mehmood, who is leading Chaudhry's legal defense.
Pakistan's interior minister, Aftab Khan Sherpao, said additional police and military units had been called in to calm the situation in Karachi.
The New York-based Human Rights Watch condemned the unrest and called on the government to take stronger steps to protect civilians.
"The sequence of events leading up to this violence ... indicates that the government, acting through its coalition partners, has deliberately sought to foment violence in Karachi," said Ali Dayan Hasan, a researcher for the group.
Human Rights Watch called it a "dark day for civil and political liberties in Pakistan."
Special correspondent Zaidi reported from Islamabad and Times staff writer King from Istanbul, Turkey.