Pakistan's president said his intelligence agencies believe Osama bin Laden may be dead, but he added there is no proof. Other Pakistani officials and a US counterterrorism official said they thought the al-Qaida chief is alive. US officials said Monday that bin Laden is most likely hiding in the mountains along Pakistan's border with Afghanistan, in particular the lawless tribal regions. "We continue to believe that bin Laden is alive," said the US official, who declined to be named because he was not authorized to discuss the matter on the record. Reports of bin Laden's death or of near-captures have punctuated his years on the run since the Sept. 11, 2001 attacks, only to be seemingly debunked by periodic audio and video recordings. The latest recording emerged in March, in which bin Laden referred to the December-January Israeli offensive in the Gaza Strip, calling it a "holocaust," and spoke of the January election of Somalia's UN-backed president, calling for him to be overthrown. In an interview Monday with international media outlets, Pakistani President Asif Ali Zardari said American officials had told him they do not know where bin Laden is. "They are much more informed," Zardari said. "They've been actually after him for a longer time. They've got more equipment. They've got more intelligence. ... so they tell us they have no trace at the moment." Zardari added that his country's intelligence agencies "obviously feel that he does not exist anymore," but he didn't explain how or when they reached that conclusion, and quickly qualified his comment by saying bin Laden "may be dead." "That's not confirmed. We can't confirm that," he said. "It's still in between fiction and fact." Prime Minister Yousuf Raza Gilani, appearing later Monday with his visiting British counterpart at a news conference, seemed surprised when a reporter asked about Zardari's remarks. "I don't know what are the comments of the president, but at the same time, I must clarify this, that nobody knows about Osama bin Laden," Gilani said. "We don't know about it, whether he is alive or dead." Mahmood Shah, a former security chief in the tribal regions, said he believes bin Laden is alive. "Where, I don't know. If he had died, we would have heard a lot of noise among the militants. From that I'd guess that he is alive," he said. Ben Venzke, director of IntelCenter, the US contractor that tracks extremist propaganda, said it was unlikely al-Qaida would keep bin Laden's death a secret. "Bin Laden's death will likely be celebrated by the group and its affiliates as him having achieved martyrdom as opposed to the group seeing it as a crushing and demoralizing blow," Venzke said.