Taliban spokesmen have denied reports the movement's supreme leader Mullah Omar has died.
The spokesmen say their phones had been hacked and false text messages sent out.
One of the spokesmen, Zabiullah Mujahid, accused "American intelligence" of being behind the false reports and vowed revenge.
The messages came from phone numbers used in the past by both Mujahid and a second spokesman Mohammad Qari Yousuf and said "spiritual Leader Mullah Mohammad Omar Mujahid has died" and "May Allah bless his soul".
The death of Mullah Omar was reported in May, by media including Afghanistan's private TV station TOLO.
That report was widely dismissed by security officials in Pakistan and diplomats, U.S. military commanders and government officials in Afghanistan.
The one-eyed, reclusive leader is one of the most wanted men in the world, and is believed to be living in Pakistan, probably in the city of Quetta.
Pakistan and the Taliban movement both deny this and say he is in Afghanistan.
compiled from agency reports