About 40 Islamic students have been detained amid continuing tension over two policemen being held hostage at a mosque in the Pakistani capital
Officials say the students are being held to stop them from going to the Red Mosque in Islamabad to support those who seized the policemen on Friday.
Two of a group of kidnapped policemen were released on Saturday.
Clerics say the remaining ones will be released in exchange for several students being held for some months.
The Lal Masjid (Red Mosque) mosque and a seminary attached to it has campaigned for strict Islamic law to be enforced in Pakistan.
Interior Ministry spokesman Javed Iqbal Cheema was quoted by the Associated Press news agency as saying that some people were "intercepted" to stop them from going to the Red Mosque.
"The government is not planning any operations against the seminary or the mosque," Mr Cheema told Reuters.
"We will not let things get out of control. They are not enemies, but our own people, and we hope this will be settled through dialogue," he said.
Mr Cheema said the detained students were expected to be freed later, but did not give any details.
A defiant Maulana Abdul Aziz, chief cleric of the mosque, threatened "jihad" or holy war if the authorities raided the mosque.
Reuters reported Maulana Aziz as saying, "We are ready to fight, we are ready to die, but we will not back down."
On Saturday, dozens of students from the Lal Masjid seminary seized the four policemen and took them inside, demanding the release of 11 students detained by intelligence agents.
After a judge released three seminary students, whom mosque officials said had been illegally detained by Pakistani intelligence agents, two of the abducted policemen were set free.
A cleric at the seminary, Abdul Rashid Ghazi, said the four policemen were taken in as they were outside the Lal Masjid in violation of an agreement with authorities that police would not be deployed there.
He said the other two policemen would be released soon.
Chief cleric Abdul Aziz announced in April that a Taleban-style Islamic court would be set up to curb "vulgar" activities.
He also demanded that the government close video shops and brothels.
Female students from the mosque seized a woman in March alleging she ran a brothel. She was later freed unharmed.
Critics of Pakistani President Pervez Musharraf say he has not done enough to act against pro-Taleban Islamic hardliners in Pakistan.
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