PESHAWAR- The head of the Pakistani Taliban is making a last-ditch bid to stamp his authority on the increasingly divided insurgency by ordering a top commander sacked, Taliban sources said today.

Taliban head Maulana Fazlullah moved against Khan "Sajna" Said on Friday after weeks of bloody infighting in the powerful Mehsud tribe that supplies the bulk of the Pakistani Taliban fighters, they said. Scores of men have been killed.

The risk for Fazlullah is that Said might ignore him and battle on. Said is trying to wrest control of the Mehsud tribe - with its many weapons and lucrative smuggling routes and extortion business - from rival Shehryar Mehsud.

The factional fighting has complicated attempts by the government to end the insurgency through peace talks it proposed in February. Some commanders are in favor of talks but others vowed to continue their insurgency.

"It's a test case for Maulana Fazlullah and his shura," a Taliban commander said, referring to the movement's leadership council. "It will determine their future."

"If Sajna is convinced and he stops fighting, it conveys a good message to rest of the Taliban factions," he said. "Otherwise it will be a setback for Fazlullah if Sajna refuses to obey his command."

Fazlullah has repeatedly appealed in vain to the two Mehsud rivals to stop fighting. An earlier peace deal brokered by the powerful Haqqani network of fighters fell through, undercutting the militants' ability to mount attacks against security forces.