Fresh fighting has erupted at the Red Mosque in Pakistan's capital, Islamabad, where a government siege of radical Islamists is in its fourth day.
Troops launched an assault as a group of students tried to leave the complex. Two students were killed, bringing the death toll to 21.
But President Pervez Musharraf has held back from a full assault, fearing casualties among women and children.
Earlier the mosque's deputy leader said he would rather die than surrender.
The BBC's Shoaib Hasan in Islamabad says a group of students tried to break out of the complex, sparking a co-ordinated assault on three sides by armoured personnel carriers and rangers.
Two students were killed in an exchange of fire and at least 10 wounded, four of them seriously.
But our correspondent says the clashes have died down and this has not been a full-scale attack.
Mosque deputy leader Abd
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