Pakistani and US officials say they are quite certain Pakistani Taleban chief and Al-Qaeda cohort Baitullah Mehsud was killed in a missile strike by a US drone in the South Waziristan tribal region last week. But senior Taleban commanders deny their leader is dead. It is difficult to independently verify the claims and counter-claims as the missile strike by a pilotless US drone aircraft took place in the Mehsud tribal lands of South Waziristan, a remote, Taleban-controlled area of northwest Pakistan. Analysts say the government will be maximizing any opportunity in a fluid situation to demoralize the Taleban and create rifts between rival factions while the question of Mehsud's successor remained open. If Mehsud is dead, analysts said the Taleban's reluctance to admit he had been killed was probably aimed at closing ranks to reinforce unity and reduce anxiety within the movement while the leadership chose a replacement. Here are the accounts given by Pakistani and Taleban officials in favor of their claims. Where is the proof of death? Pakistani officials say credible intelligence reports suggested that Mehsud, the government's public enemy number one, was killed along with his wife when two missiles fired by a US drone hit the house of his father-in-law in the Makeen area of South Waziristan on Aug. 5 shortly after midnight. But they say they have no material evidence to corroborate their claim. Speaking in parliament late Monday, Interior Minister Rehman Malik said Mehsud was being medically treated for a stomach ailment at the house of his father-in-law when the missiles struck. “A paramedics staff, who provided treatment to Baitullah on that night, said he left him on the rooftop of the residence after injecting a drip to him,” the official Associated Press of Pakistan quoted Malik as saying. Malik said Mehsud's wife and his bodyguards were also killed. “According to a credible evidence, Baitullah Mehsud is dead but we are trying to work out evidence in terms of DNA tests and statements of family members,” the minister said. US National Security Adviser Jim Jones said there were “pretty conclusive” reasons to believe Mehsud had been killed. “We think so. We put it in the 90 percent category,” Jones told NBC's “Meet the Press” when asked if Mehsud had been killed. Three senior aides to Mehsud, including two possible successors, say he is alive. The government's credibility was questioned after it fanned reports that there had been a shootout between two rival Taleban commanders at a meeting to choose Mehsud's successor as leader of the Pakistani Taleban. Both commanders, Wali-ur-Rehman and Hakimullah Mehsud, subsequently called journalists to deny there had been any shootout, and show that, contrary to reports, neither of them was dead. Hakimullah said, “If the interior minister failed to prove Baitullah Mehsud's death, then I will produce evidence that he is alive.” Mehsud deputy Noor told that a video would soon be released to prove Baitullah was alive. However, Hakimullah and Wali-ur-Rehman, another possible successor to Mehsud, conceded that Mehsud, who suffers from diabetes, has been ill, raising suspicions that they are merely preparing the ground for announcing a successor without conceding Mehsud's death. Wali-ur-Rehman said Mehsud had not been looking after the Taleban's affairs for the past three months.