The family of hostage Matan Angrest released a photograph on Monday evening showing him in captivity.
The photo is the first visual documentation of Angrest and was released six months after Hamas published an audio recording of him.
"This is the first footage from a video of Matan Angrest, a soldier who was kidnapped while wounded and unconscious from a tank at the Nahal Oz outpost," his family said in a statement.
"He had gone out with his team to defend the outpost and the kibbutzim. Matan was abducted in critical condition and is enduring unimaginable suffering, torture during interrogations, and inhumane conditions. Despite being severely wounded, he was not returned in the humanitarian phase, solely because he is an Israeli soldier."
"We demand that the Israeli government complete all stages of the deal before proceeding with the next phase of the war and bring Matan—who is in mortal danger—and all the hostages home before sending more soldiers who may never return," Matan's mother said in a statement.
The photo is a still image from the video from which the initial audio originated. Hamas released it as a sign of life.
Angrest, who served in a tank unit, was captured alongside his fellow soldiers Itai Chen, Daniel Peretz, and Tomer Leibovitz - all of whom were killed in the battle.
Their bodies were also taken into Gaza. According to the Hostage Family Forum, Angrest was critically wounded when he was captured.
What was said in the audio?
Angrest addressed Prime Minister Benjamin Netanyahu in the video, urging him to secure his release. "Netanyahu, you must make the exchange between the prisoners in Israel and the prisoners here," he said. "I believe you're capable of it; you just need to want it."
"Netanyahu, I trust you! You can do it, and I hope it will happen as soon as possible," Angrest can be heard saying.