Mehsud's death "is a signal achievement for the covert CIA programme at a time when drones themselves have come under criticism from human rights groups and other critics in Pakistan and the United States over the issue of civilian casualties," the influential New York Times said in a report from London.
The Washington Post agreed that if confirmed it "would be a victory for US officials who have spent years hunting down a leader implicated in a 2009 attack that killed seven Americans at a CIA outpost in eastern Afghanistan."
But it suggested that while the event "could cripple the group" it may "undermine an effort by Pakistan's government to engage militants in peace talks" and "add to strains between the United States and Pakistan."
The "elimination" of Mehsud "by a drone strike in Pakistan today is a significant step forward in the fight against global terrorism," said Lisa Curtis, Senior Research Fellow at The Heritage Foundation.
"The TTP has been responsible for the deaths of thousands of Pakistanis in terrorist attacks throughout the country since the group was formed in 2007," she noted.
"Mehsud was also involved in the 2009 attack on the CIA base in Khost, Afghanistan, having appeared in a video filmed before the attack with the Jordanian suicide bomber."
CNN, however, noted "This is not the first time Mehsud -- who took the reins of the Pakistani Taliban in 2009 -- has been reported killed after a drone strike. In February 2010, multiple sources said he had died after being hit in a drone strike in Pakistan a month earlier.
But reports that he was alive surfaced in April of that year, and in May 2010 he appeared in a video vowing attacks on major US cities.
Mehsud took over from Baitullah Mehsud, a fellow clan member, in 2009 after the latter was killed in a US drone strike.