Pakistan has charged three politicians and a trade union leader with treason for making speeches against President Pervez Musharraf's imposition of emergency rule.
The four were remanded in custody for two weeks by a court in the southern city of Karachi, two days after they were arrested for criticising Musharraf in addresses at the city's press club.
Treason - or sedition, as the activists have been formally charged with - carries a maximum sentence of death.
Meanwhile, authorities have rounded up hundreds of supporters of ex-premier Benazir Bhutto.
The crackdown came just hours after US President George W Bush telephoned Musharraf to urge him to repeal the state of emergency, hold elections in January and quit as army chief of the nuclear-armed Islamic republic.
A statement by Pakistan's attorney general that elections would be held by February and the state of emergency lifted in one or two months failed to quell the mounting tension.
'Elections will be held in February, it has been decided,' attorney general Malik Mohammad Qayyum, the government's chief lawyer said. 'The emergency will be lifted in one or two months.'
Musharraf imposed the state of emergency on Saturday citing growing Islamic militancy and a meddlesome judiciary. He suspended the constitution, sacked the chief justice and clamped curbs on the media.
The move has sparked days of sporadic protests and led to more than 3,000 arrests, the latest involving supporters of Bhutto's Pakistan People's Party (PPP).
'Well over 600 party activists have been arrested and many of our leaders have gone underground. The crackdown is continuing,' senior party leader Raza Rabbani said.
Police sources confirmed the arrests of only 140 PPP workers.
Bhutto has pledged to rally supporters in the garrison city of Rawalpindi tomorrow and stage a 'long march' next week if Musharraf does not meet her demands, which mirror those of the international community.
