The military authorities in Pakistan say they have arrested at least three army officers on suspicion of having links with Islamic extremists.
The head of the armed forces public-relations department, Major-General Shaukat Sultan, told the BBC the arrested officers were being interrogated by the army's intelligence unit.
Musharraf has ordered a crackdown on Islamic extremists
This is the first known case of its kind since President Pervez Musharraf ordered a crackdown against Islamic extremist groups in the country almost two years ago.
The arrests were made public as the Pakistani military authorities stepped up their operation against the Taleban in the country's border region.
But it is not clear if the arrested officers were in any way involved in regrouping the remnants of the Islamic militia.
One of the arrested army officers has been identified as Lieutenant-Colonel Khalid Abbassi.
At the time of his arrest, he was posted in the town of Kohat, close to the border with Afghanistan.
Other arrested officers are in the junior ranks.
Major-General Sultan said the army's field intelligence unit is interrogating the officers about their possible links with extremist groups.
The Taleban used to have Pakistan's official support
He refused to identify the groups but said action was being taken against the arrested officers under the army's strict disciplinary rules.
A number of militant groups having affiliation with the Taleban or involved in sectarian violence were banned and scores of their members arrested.
It is widely believed that several officers of the Pakistani army developed sympathy with the Taleban when Islamabad was officially backing the Islamic militia.
Although Pakistan's official policy towards the Taleban changed after the events of 11 September 2001, there was no significant purge within the army.
But following recent concerns expressed by Washington and Kabul about Taleban remnants trying to regroup in the Pakistani border region, the authorities have increased vigilance, and in the last couple of days at least 18 suspected Taleban fighters have been arrested in the border area