''Musharraf's days are numbered. The time has come to end the political role of the army,'' Javed Hashmi, acting president of the Pakistan Muslim League (Nawaz), told reporters before being whisked away by police in the central city of Multan.
In Karachi, the country's largest and most politically volatile city, police chief Azhar Ali Farooqi spelled out the uncompromising stand that has been ordered.
''Our soft policy is over now. We have zero tolerance. We will take action, arrest and use force if necessary,'' Farooqi said, as attention turned to what Pakistan's most potent opposition leader, Benazir Bhutto, might do next.
Bhutto, who ended 8 years of self-imposed exile last month with Musharraf's blessing, returned to Karachi yesterday evening after a short trip to Dubai and took a strong stand against what she called a ''mini-martial'' law.
But the litmus test will be whether she calls for street protests or seeks to persuade Musharraf to reverse his decision.
Qazi Hussain Ahmed, the leader of an alliance of Islamist opposition parties and fierce Musharraf critic, planned to address a public meeting outside the eastern city of Lahore later today.
Tariq Mehmood, a leading anti-Musharraf lawyer, said most lawyers opposed to the military ruler were under house arrest or detained.
''It's the second takeover of the country by General Musharraf since 1999. He has not imposed emergency rule but has imposed martial law,'' Mehmood told Reuters from a police station where he was detained.
Police placed leading opposition figure and former cricket star Imran Khan under house arrest early today after he urged Pakistanis to take to the streets.
Khan told CNN Musharraf was to blame for Pakistan's problems and said emergency rule would not help.
''He never said how is he, through the emergency, going to do things that are any different. He was the absolute ruler, he had absolute control, so what was the impediment in his way to fight militancy and terrorism?'' Leading lawyer and opposition figure Aitzaz Ahsan was one of the first to be detained yesterday.
''They have served me a detention order for 30 days,'' Ahsan, president of the Supreme Court Bar Association, told reporters outside his home in the capital.
''One man has taken entire nation hostage... Time has come for General Musharraf to go,'' he said.
Several opposition figures and anti-Musharraf lawyers were also arrested in the southwestern city of Quetta, police said.