Hamas has told Israel that eight of 26 Israeli hostages set to be released as part of the first phase of the ceasefire are dead, a Middle Eastern official briefed on the matter told NBC News on Monday.

It is believed to be the first time that the militant group has said exactly how many hostages are dead or alive. Later, a spokesman for Prime Minister Benjamin Netanyahu said these numbers matched information gleaned by Israeli intelligence.

The first three Israeli hostages — Romi Gonen, Doron Steinbrecher and Emily Damari, a dual British citizen — were freed earlier this month in exchange for 90 Palestinian detainees — mostly women and children.

On Saturday, four female Israeli soldiers were released in exchange for 200 Palestinian prisoners, many of whom were serving life sentences after being convicted of deadly attacks.