Palestinians mourn their relatives killed in the Israeli bombardment of the Gaza Strip, at the hospital Rafah, southern Gaza. AP
Abu Obeida, the spokesman for Ezzedine al-Qassam Brigades, also said in an audio recording that any further release of hostages held in Gaza depended on a "cessation of aggression".
Neither Israel's continued offensive nor "direct military operations" would bring the hostages home, he said.
"It is not possible to release enemy prisoners alive except by entering into negotiations."
According to Israeli authorities, 129 captives remain held in Gaza.
Abu Obeida said there was "no alternative" to negotiations, warning that Israeli fire could lead to the deaths of more captives.
He aimed at Israel's leader, whose "decision... evades facing and recognizing the truth".
Shortly after the spokesman's recording, Hamas's armed wing also released a video showing three Israeli captives, claiming they had since been killed in Israeli strikes.
The bloodiest ever Gaza war began when Hamas attacked Israel on October 7, taking some 250 captives and killing around 1,140 people, mostly civilians inside Israel, according to an AFP tally based on official figures.
Israel's retaliatory bombardment and ground invasion has killed at least 20,000 people, two-thirds of them women and children, according to the Gaza government.
A truce last month led to the release of over 100 captives including 80 Israelis in exchange for 240 Palestinians held in Israeli prisons.
The head of the Palestinian militant group visited Egypt this week, raising hopes for another truce and deal to free the remaining captives, though talks have yet to produce a new agreement.
Short link: