Reports of the likely death of Saleh al-Somali, a Somali-born key al Qaeda operational planner, in a U.S. drone strike in northwestern Pakistan Tuesday prompted at least one knowledgeable Arab diplomat in the country to describe him as "a lynchpin in al Qaeda's well-considered new strategy."
According to the diplomat who spoke to CBS NEWS on condition of anonymity, al-Somali's responsibilities included plotting al Qaeda's attacks and plans beyond the Afghanistan-Pakistan region.
"Since the summer of 2008, I believe he was involved with planning to shift some of al Qaeda's Arab fighters to Yemen" - the conservative state in the Arabian peninsula alongside Saudi Arabia's southern border, where al Qaeda has pushed an increasingly violent insurgency in the past year.
The diplomat said that between one-quarter to one-third of al Qaeda's units in the Afghanistan-Pakistan region are now led by non-Arabs, in a transition from "100 percent of these units which were once led by Arabs."
He said militants from the central Asian former Soviet republic of Uzbekistan and Afghanistan were now either "holding permanent or temporary charge of these units," as some of al Qaeda's most hardened fighters head out of the region for Yemen, which he described as "their new frontier."
A Pakistani security official with knowledge of al Qaeda's operations, who spoke to CBS News on condition of anonymity, said, "Saleh al-Somali's killing will be a major setback for an outfit which does not necessarily document all of its operational details. In this shady world, individuals keep part of the information to themselves, which means that if they vanish, there is a gap."
A second Arab diplomat who also spoke to CBS News on condition of anonymity said that the exit of Arab militants from the Afghanistan-Pakistan area "will now weaken al Qaeda's presence or stand here. They are simply trying to move resources which they consider are of the right kind to a new conflict" in Yemen.
The diplomat also revealed some intelligence reports which suggested that al-Somali had traveled to Yemen in the past year to get a firsthand look at the situation there.
"There was always a bit of a time lag in this information, so it was impossible to target him," said the second Arab diplomat. "But eventually, his killing has proved that al Qaeda is becoming increasingly vulnerable."
CBS News' Farhan Bokhari reported from Islamabad.