Washington, May 4 (IANS): Osama bin Laden ordered suicide squads to be created in Pakistan and Afghanistan to track down US President Barack Obama and then NATO commander Gen. David Petraeus, according to a treasure trove of his letters.

Bin Laden's directions about Obama and Petraeus come in a May 2010 letter, one of 17 released by the US military's West Point Combating Terrorism Centre from the documents captured in the raid on the Al Qaeda leader's hideout in Pakistan last May.

Bin Laden asked his lieutenants to identify people in both countries who could keep an eye out for Obama and Petraeus and conduct suicide operations against them as they travelled in either country.

"I asked Shaykh Sa'id, Allah have mercy on his soul, to task brother Ilyas to prepare two groups - one in Pakistan and the other in the Bagram area of Afghanistan - with the mission of anticipating and spotting the visits of Obama or Petraeus to Afghanistan or Pakistan to target the aircraft of either one of them," bin Laden wrote.

He then gave a brief civics lesson on why they should not target Vice President Joe Biden: because he was in the direct chain of command and "Biden is totally unprepared for that post (the presidency), which will lead the US into a crisis," he wrote.

He also said the suicide teams were not to target then Secretary of Defence Robert Gates or the chairman of the Joint Chiefs of Staff at the time, Admiral Mike Mullen, or Richard Holbrook, who was the special envoy to Pakistan and Afghanistan. Bin Laden's reasoning for targeting only Petraeus and Obama was that they were the heads of state and of operations in Afghanistan, and without them, the path of the war would be altered.

In its executive summary on the documents, the US military says they reveal Bin Laden's frustration with affiliated organisations and his powerlessness to control their actions.

For one, his lieutenants threatened to take measures against the leadership of the Pakistani Taliban for their "vile mistakes", including indiscriminate attacks on Muslims.

The letters reveal that Bin Laden was also sceptical of so-called lone wolf missions by home grown jihadists as the "percentage of success was low due to psychological factors that affect the (designated) brother in such a situation".

He urged his associates "not to send a single brother on a suicide operation; they should send at least two"