Pakistani and Afghan officials say two US drone strikes in the tribal regions bordering Afghanistan have killed 13 people, including a senior militant commander who had a truce with Pakistan's military.

Government and intelligence officials told CBS News that two missile strikes occurred early Thursday in the South and North Waziristan tribal areas.

They said the commander, Maulvi Nazir, was reportedly among nine people killed in the first strike in the village of Angoor Adda in South Waziristan. A senior government official in Peshawar, the largest city near the tribal areas, confirmed Nazir's death to CBS News' Farhan Bokhari.

Residents in both Angoor Adda and Wana, the biggest town in South Waziristan, said they heard announcements on mosque loudspeakers announcing Nazir's death.

Bokhari said Nazir's death brought warnings that tension between the US government and Pakistan, a difficult but vital ally in the war on Islamic extremism, could worsen.

The powerful militant commander was seen as an ally of Pakistan's security forces. Since 2011, he was reportedly behind a number of attacks targeting Western forces in Afghanistan, while simultaneously waging war against Taliban militants fighting Pakistan's army in the border region.

"Maulvi Nazir was seen as an asset by some Pakistani security circles," a senior Western diplomat in Islamabad told CBS News, suggesting his death would, "strain Pakistan's relations with the United States"...

An Afghan intelligence official, and a Pakistani Taliban sub-commander, who told CBS News' Sami Yousafzai he served under Nazir, also acknowledged his death. The sub-commander lauded Nazir as "a committed jihad commander and tribal elder" and said his demise was a, "big blow for the Wazir tribe and jihad in Afghanistan."

The sub-commander said Nazir had not been "fighting against the Pakistani army under current circumstances," and his priority was "wining jihad against the US and NATO forces in Afghanistan."

The Afghan intelligence source told Yousafzai that Nazir had been organizing Afghan and Pakistani militants -- in an "understanding" with Pakistan's ISI intelligence agency -- and sending them across the border to fight in Afghanistan.

The ISI is regularly accused of maintaining links to several Islamic militant groups in Pakistan, though the agency insists all historic links with the groups have been severed.

READ FULL SOURCE ARTICLE: 01/03/2013