KABUL, Afghanistan (AP) -- The beat-up video camera was delivered to Afghanistan in a box, and picked up by two clean-shaven Arabs posing as journalists. They met with Osama bin Laden before leaving on their mission - to kill mujahedeen hero Ahmad Shah Massood.

Five years after the Taliban opponent was slain by a bomb hidden in the camera, a former Taliban official on Saturday described how al-Qaida staged the killing - two days before the Sept. 11 attack on America - hoping to strike a fatal blow to the pro-U.S. Northern Alliance.

Waheed Mozhdah, director of the then-Taliban Foreign Ministry's Middle East and Africa department, also showed The Associated Press a copy of what he said was a signed letter dated Sept. 13, 2001, from bin Laden to Taliban leader Mullah Omar, urging him to launch an offensive against the alliance.

In the letter, written in Arabic, bin Laden said that if America failed to respond to the Sept. 11 attacks, it would decline as a superpower. But if the U.S. started fighting, he added, its economy would suffer a major blow and it would face the same destiny as the Soviet Union - whose ill-fated 1980s occupation of Afghanistan heralded its disintegration.

Few details have emerged previously about how al-Qaida plotted to murder Massood, the "Lion of Panjshir" who fought Soviet troops and led resistance to the Taliban regime. At the time, his Northern Alliance was under siege, barely clinging to a mountainous northern corner of the country.

But the U.S. military campaign after Sept. 11 to punish the Taliban for giving refuge to bin Laden propelled Massood's supporters to power, and the bearded commander has achieved iconic status. Giant portraits of him adorn government offices and public spaces in Kabul, and the Sept. 9 anniversary of his death is marked in grand style.

President Hamid Karzai on Saturday addressed a crowd of thousands at a Kabul stadium attending an official Massood commemoration.

"They came from outside to kill him. They put a bomb inside a camera pretending they wanted to interview him. Why did they kill him? Because he said they would defeat them," he said.

The attackers apparently were North African Arabs traveling on forged Belgian passports who managed to pass through the front line between the warring Taliban and Northern Alliance carrying their bomb.

"We never suspected journalists. Our leaders were careless," said Massood Khalili, a former Massood adviser who was seriously wounded in the blast.

One of the Arabs died in the bombing. The other, who survived the blast, was shot dead by enraged bodyguards.

Mozhdah said bin Laden appeared to hint at the plot during a meeting with Taliban Information Minister Amir Khan Muttaqi in the southern city of Kandahar - the seat of the ousted Taliban regime - just after the Islamic fasting month of Ramadan in 2000.

Citing an account provided by a translator at the meeting, Mozhdah said bin Laden complained to Muttaqi about Taliban restrictions that prevented al-Qaida from contacting the media. "My hands are tied behind my back and my mouth is taped shut," an annoyed bin Laden reportedly said.

When Muttaqi blamed international pressure - including sanctions - facing the Taliban regime for hosting al-Qaida bases and fighting the Northern Alliance, bin Laden thought for a while before replying, Mozhdah said.

"I know your difficulties. I'm looking at how to solve your problem," the al-Qaida leader said, without elaborating, according to Mozhdah.

Mozhdah said that the following spring - he was unsure of the precise date - a parcel from Pakistan was received at an official media office used by al-Qaida and the Taliban in Kandahar.

The box looked new, but it contained a rather old-looking video camera, Mozhdah said, and the computer technician at the office expressed puzzlement about it. A day later, he said, it was picked up by an al-Qaida official accompanied by two Arabs with shaven faces - a curious sight in Taliban-dominated Afghanistan, where men were made to wear beards.

The Arabs, known to Mozhdah only as Karim and Arbet, subsequently had the camera while purportedly taping an interview with Taliban Foreign Minister Abdul Wakil Mutawakil but never gave a requested copy to him, he said.

Mozhdah said the Arabs later met with bin Laden, top deputy Ayman al-Zawahri and Mullah Omar, who gave them a warm send-off before they flew to Kabul. There, he said, the Foreign Ministry gave them a letter of permission to cross the front line into Northern Alliance-held territory in the Panjshir Valley, Massood's domain north of the capital.

To win acceptance on the other side, the journalists had an introduction from an Islamic group in London to Abdul Rasul Sayyaf, a Northern Alliance commander in Panjshir with strong contacts to Arab mujahedeen from the days of the Soviet resistance, said Abdullah Abdullah, another close associate of Massood.

Abdullah, who served as Afghan foreign minister until earlier this year, said this facilitated the Arabs' entry into Panjshir. Sayyaf hoped their report could help the alliance's standing in the Muslim world but also warned the commander at the front line, Bismullah Khan, now chief of Afghan army staff, "to be watchful of them," Abdullah said.

Abdullah said he saw the Arabs in Panjshir about 20 days before the assassination.

"It was a very brief encounter. When I wind my mind back, I remember their gaze was one of hatred," he said.

The journalists waited for a chance to speak with Massood. When the opportunity came, at his redoubt in the town of Khodja Bahauddin, they had 15 questions - eight of them about bin Laden.

Khalili, now the Afghan ambassador to Turkey, said that as the camera supposedly began rolling, he started to translate the first question for Massood from English - "What is the situation in Afghanistan?" - when a fireball ripped through the room.

Massood died, and Khalili spent seven days in a coma.

The death wasn't reported for six days, in fear of undermining the Northern Alliance. By the time of the announcement, the Sept. 11 attacks had transformed the world. Two months later, Massood's once beleaguered forces routed the Taliban with the support of U.S. air power.