Palestinian group Hamas said on Thursday that a militant in Gaza who executed an Israeli hostage acted "in revenge" after hearing his children had died in an Israeli attack.
The Israeli military said an image released by Hamas along with its statement showed a dead hostage whose body had already been retrieved from Gaza by Israeli forces last year.
The Ezzedine al-Qassam Brigades, the armed wing of Hamas, announced on Monday that an Israeli hostage was killed and two others wounded in separate shooting "incidents".
The group said in a statement on Thursday that its investigation into the Israeli man's death in captivity had found that "a conscript assigned to guard (the hostage) acted against orders in revenge, after receiving news of the martyrdom of his two children in one of the enemy's massacres".
Out of 251 captives seized by Palestinian fighters during Hamas's October 7 attack, 111 are still held in the Gaza Strip including 39 the Israeli military says are dead.
The photograph released by the Hamas armed wing along with its latest statement showed a dead man covered in a blood-stained white shroud, without identifying him.
The statement described his death as an "unfortunate incident", blaming the "brutality" of the Israeli military campaign for it.
"Your brutality has become an imminent danger to your prisoners," Hamas said.
Hamas's latest statement made no mention of the second incident reported on Monday, in which the Ezzedine al-Qassam Brigades had said two other hostages, both women, were shot and wounded.
Israel's military campaign in Gaza has killed at least 40,005 Palestinians in the Gaza Strip since October 7, in a war that has been ongoing for over 10 months. Israel's atrocities in the Gaza Strip have been labelled as genocide and war crimes by experts, UN agencies and several world leaders.
International mediators have invited the warring sides for negotiations on Thursday in Qatar, seeking a truce in Gaza and a hostage release deal.