The announcement's came shortly after Pakistani state television reported that Mehsud died in Orakzai, an area in Pakistan's northwest tribal region.
Army spokesman General Athar Abbas said, "We have these reports coming to us. We are investigating whether it is true or wrong."
Pakistani intelligence officials said that they have confirmation that the Taliban chief's legs and abdomen were wounded in the strike.
Mehsud was targeted in a US drone strike in South Waziristan on Jan 14, triggering rumours that he had been injured or killed.
However, the chief Taliban spokesman dismissed the reports again on Sunday, Jan 31.
"Hakimullah is alive and safe. The purpose of stories regarding his death is to create differences among Taliban ranks, but such people will never succeed," Azam Tariq was quoted by news agency over phone as saying.
"People who are saying that Hakimullah has died should provide proof of it. We have already proved that he is alive and we have provided two audio tapes of him to all the media," he said.