Spin Boldak, Afghanistan: Osama Bin Laden, if he's alive, celebrated his 50th birthday yesterday, and his friends in the Taliban prayed for his long life.

The Al Qaida leader's long silence has fuelled speculation the world's most-wanted fugitive may have died, though many in the international intelligence community reckon militant websites would circulate word of his death.

"He is alive. I am 100 per cent sure," said Taliban spokesman Mullah Hayatullah Khan, adding senior leaders were in touch with Bin Laden, reinforcing a widely held view that he is hiding near the rugged Pakistan-Afghanistan border.

Khan said special prayers were offered by Taliban fighters in camps in Afghanistan to mark Bin Laden's birth on March 10, 1957, in the Saudi Arabian city of Jeddah.

"We prayed that Allah may give him 200 years to live," Khan said by satellite telephone from an undisclosed location.

Video tape

"When we woke up today, we offered collective and long prayers for him because he is a great mujahid (holy warrior)."

The most recent videotape of Bin Laden was released in late 2004 - subsequent tapes released were identified as old footage - and around half a dozen audio tapes surfaced in the first half of 2006.

But a long silence since then has fuelled rumours that Bin Laden is unwell, or dead, though the United States fears the Al Qaida network he founded is rebuilding its base in Pakistani tribal lands.

CIA send additional spies to Pakistan

The CIA is dispatching additional spies and paramilitary officers to Pakistan in an attempt to force Osama Bin Laden into making a mistake that could lead to his capture or death, according to American officials.

Satellite photographs and details of communications intercepts were given to President Musharraf of Pakistan last week by Stephen Kappes, deputy director of the CIA, as part of a strategy to persuade him to give US intelligence agencies more assistance.