Ayman al-Zawahari, Al Qaeda [Images] leader and Osama Bin Laden's deputy, secretly directed the Islamic militants whose armed revolt at Lal Masjid in Islamabad ended last week with a bloodbath after the Pakistan Army stormed it, a media report said on Sunday.

The troops who finally took control of the mosque discovered letters from al-Zawahari, The Sunday Times said, quoting senior intelligence officials.

The letters were written to Abdul Rashid Ghazi and Abdul Aziz, the brothers who ran the mosque and adjacent madrassa.

Government sources said up to 18 foreign fighters -- including Uzbeks, Egyptians and several Afghans -- had arrived weeks before the final shootout and set up firing ranges to teach students, including children, how to handle weapons.

Al Qaeda has wanted to open a Pakistan front in its global campaign since President Pervez Musharraf [Images] sided with America after the terrorist attacks of September 11, 2001.

Diplomats were surprised by the speed with which the fugitive Zawahiri condemned the raid and called on Pakistanis to rise up against Musharraf.

The response to his appeal was equally swift. Twenty-seven soldiers were killed when a suicide attacker struck a military convoy in north-west Pakistan near the Afghan border on Sunday.

At least 58 have been killed in bombings and shootings since the Lal Masjid crisis began 12 days ago.

This weekend street protests were organised by religious parties as the government dispatched thousands more soldiers to its troubled North West Frontier Province.