ISLAMABAD - The Pakistani Taliban appointed a new chief -- a top commander known for his ruthless efficiency in staging attacks, including a major hotel bombing and a deadly assault against the Sri Lankan cricket team.

The appointment of 28-year-old Hakimullah Mehsud could herald an increase in attacks as the group tries to prove it is still intact and operational, analysts say. It comes after weeks of speculation and reported infighting among Taliban commanders to replace Baitullah Mehsud, the group's former chief who was reportedly killed in an Aug. 5 CIA missile strike in northwestern Pakistan.

Several top Taliban commanders have insisted Mehsud is alive, but have provided no proof. U.S. and Pakistani officials say they are almost certain he was killed in the strike.

Two close aides to another commander, Maulvi Faqir Mohammad, told The Associated Press on Saturday that a 42-member Taliban council, or shura, appointed a new head because Baitullah Mehsud was ill.

"I do confirm that a shura held Friday ... has elected Hakimullah Mehsud (as) the new chief of the Taliban," said one of the aides, Bakht Zada, adding it was an unanimous decision. "Now all these talks of differences should end. There have not been any differences ever."

Pakistan's Taliban is a loose alliance of disparate groups and tribal factions that Baitullah Mehsud had managed to unify. If true, the selection of Hakimullah Mehsud is could shore up an organization reeling from the loss of its leader, said Kamran Bokhari, director of Middle East analysis with Stratfor, a global intelligence company.

"It's an attempt to stabilize the group after the initial reports of infighting," Bokhari said, noting the loss of Baitullah would have been "a massive blow to the organization."

As military chief of Baitullah's Tehrik-e-Taliban Pakistan, or Pakistani Taliban Movement, Hakimullah commanded three tribal regions and has a reputation as Baitullah's most ruthless deputy. He was considered one of the top contenders to take over. He first appeared in public to journalists in November 2008, when he offered to take reporters on a ride in a U.S. Humvee taken from a supply truck heading to Afghanistan.

Authorities say he was behind threats to foreign embassies in Islamabad, and there was a 10 million rupee ($120,000) bounty on his head.

Hakimullah claimed responsibility for the June 9 bombing of the Pearl Continental hotel in Peshawar, and the attack on the Sri Lankan cricket team in Lahore earlier this year.

He also threatened suicide bombings in Pakistani cities in retaliation for a recent army offensive in the Swat Valley, which has been winding down in recent weeks.

While it is unclear whether he will be able to maintain unity, he was likely chosen for his operational capabilities, said Bokhari, adding a revival of suicide bombings could be expected.

More attacks would demonstrate that the Pakistani Taliban was intact and able to operate despite recent setbacks, he said. "I think that the decision of the shura to appoint this particular individual is based on that consideration."

Interior Minister Rehman Malik said the government had received intelligence reports about Hakimullah's appointment "as the chief terrorist" but there was no official confirmation.

Another close Mohammad aide, Sher Zamin, also confirmed that Hakimullah had been elected as the new Taliban chief.