ISLAMABAD, Pakistan (CNN) -- Hours after declaring a state of emergency Saturday, Pakistani President Pervez Musharraf ordered troops to take a television station's equipment and put a popular opposition leader under house arrest.
President Pervez Musharraf explains his actions in a televised address Saturday.
Musharraf also suspended the constitution and dismissed the Pakistan Supreme Court's chief justice for the second time.
On Sunday, police arrested the Javed Hashmi, the acting president of ex-Prime Minister Nawaz Sharif's opposition party was arrested, along with 10 aides, The Associated Press reported. Hashimi was arrested when he stepped outside his house in the central city of Multan, AP reported.
The country is at a critical and dangerous juncture -- threatened by rising tensions and spreading terrorism, Musharraf said in a televised address to the nation after declaring martial law.
As Pakistani police patrolled the streets of the capital, Islamabad, Musharraf said his actions were "for the good of Pakistan." Watch Musharraf's speech »
There was quick condemnation from within and outside his country.
The Supreme Court declared the state of emergency illegal, claiming Musharraf -- who also is Pakistan's military chief -- had no power to suspend the constitution, Chief Justice Iftikhar Mohammed Chaudhry said.
Shortly afterward, government troops came to Chaudhry's office and told him the president had dismissed him from his job.
Justice Abdul Hameed Dogar was quickly appointed to replace him, according to state television.
It was the second time Chaudhry was removed from his post. His ousting by Musharraf in March prompted massive protests, and he was later reinstated. See a timeline of upheaval in Pakistan »
Musharraf complained in his speech that the media -- which he made independent -- have not been supportive, but have reported "negative" news.
Early Sunday, two dozen policemen raided the offices of AAJ-TV in Islamabad, saying they had orders to take the station's equipment.
The government also issued a directive warning the media that any criticism of the president or prime minister would be punishable by three years in jail and a fine of up to $70,000, said Talat Hussain, director of news and current affairs for AAJ. Watch a former Pakistani P.M. call the developments in his country 'disturbing' »
U.S. Secretary of State Condoleezza Rice -- who is in Turkey for a conference with Iraq and neighboring nations -- said The United States doesn't support any extra-constitutional measures taken by Musharraf.
"The situation is just unfolding," Rice said. "But anything that takes Pakistan off the democratic path, off the path of civilian rule is a step backward, and it's highly regrettable."
A senior Pakistani official said the emergency declaration will be "short-lived," and will be followed by an interim government.
Martial law is only a way to restore law and order, he said.
Mahmud Ali Durrani, Pakistan's ambassador to the United States, agreed.
"I can assure you, he will move on the part of democracy that is promised ... and you will see that happen shortly."
Musharraf was re-elected president in October, but the election is not yet legally official, because the Supreme Court is hearing constitutional challenges to Musharraf's eligibility filed by the opposition.
Under the constitution, Musharraf couldn't run for another term while serving both as president and military leader.
The court allowed the election to go ahead, however, saying it would decide the issue later.
Some speculated that the declaration of emergency is tied to rumors the court was planning to rule against Musharraf.
Musharraf has said repeatedly he will step down as military leader before the next term begins on November 15 and has promised to hold parliamentary elections by January 15.
Meanwhile, popular opposition leader Imran Khan said early Sunday that police surrounded his house in Lahore, barged in and told him he was under house arrest.
Musharraf also had Khan placed under house arrest during a government crackdown in March 2006.
Asked about Musharraf's actions Saturday, Khan said, "We are going to oppose this in every way."
"None of us accept ... this whole drama about emergency."
Former Prime Minister Benazir Bhutto -- who arrived in Karachi Saturday from Dubai, where she had gone to visit her family -- described a "wave of disappointment" at Musharraf's actions. Watch crowds surround Bhutto upon her arrival »
Bhutto -- who returned to Pakistan last month after several years in exile -- wants to lift her Pakistan People's Party to victory in January's parliamentary election in the hope she can have a third term as prime minister.
The nation's political atmosphere has been tense for months, with Pakistani leaders in August considering a state of emergency because of the growing security threats in the country's lawless tribal regions. But Musharraf, influenced in part by Rice, held off on the move. Watch a report on the volatile situation in Pakistan »
Musharraf, who led the 1999 coup as Pakistan's army chief, has seen his power erode since the failed effort to oust Chaudhry. His administration is also struggling to contain a surge in Islamic militancy. E-mail to a friend
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