'Zawahiri may not be dead in US attack'

In Pakistan, officials said earlier indications from US intelligence sources that a key lieutenant of Osama bin Laden, possibly his number two Ayman al-Zawahiri, may have died in Friday's missile raid were "not true".

Yet "in Washington, US intelligence sources said it was too early to know whether the strike had killed Zawahiri, 54, an Egyptian physician who is al-Qaeda leader Osama bin Laden's top aide," the Post said.

The paper quoted an unidentified source as saying: "The outcome of this doesn't seem decided."

In addition "US officials defended the strike, saying it was the right course of action based on timely intelligence about Zawahiri's whereabouts early on Friday. Zawahiri had been under surveillance by the CIA for two weeks, security sources said," according to the Post.