Hwange National Park said Cecil's oldest cub Xanda "has met the same fate" as his father
A son of Cecil the lion is said to have been shot during a trophy hunt in Zimbabwe.
It is claimed Xanda was shot in Hwange National Park during a hunt organised by a Zimbabwean professional hunter.
The hunter has been accused of also being involved in the killing of Xanda's brother in 2015.
In a post on Facebook, park officials said: "Xanda is still a young father at 6.2 years old and has several young cubs. We can't believe that now, 2 years since Cecil was killed, that his oldest cub Xanda has met the same fate.
"When will the Lions of Hwange National Park be left to live out their years as wild born free lions should...?"
The Daily Telegraph reports that the hunter handed the lion's collar back to researchers after realising it was being monitored.
Andrew Loveridge of Oxford University, who fitted the collar last year and has been monitoring Xanda and his pride, told the Telegraph that the hunt was "legal and Xanda was over 6 years old so it is all within the stipulated regulations".
However, the researcher said he hoped a 5km exclusion area would be introduced around the park to avoid accidental killings of monitored animals.
There was international condemnation following the killing of 13-year-old Cecil in 2015.
It was revealed that an American dentist and recreational hunter, Walter Palmer, was responsible for shooting Cecil with an arrow.
He is believed to have paid guides around $50,000 to facilitate the hunt and killing.
In a statement at the time, Palmer said he believed "everything about this trip was legal and properly handled and conducted".
He claimed: "I had no idea that the lion I took was a known, local favorite, was collared and part of a study until the end of the hunt. I relied on the expertise of my local professional guides to ensure a legal hunt.
"I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion."
Palmer ultimately did not face charges in Zimbabwe, but his actions saw a global backlash significant protests outside his dentistry practice in Minnesota .