Two Tanzanians and a South African are among the 224 hostages being held by Hamas after the 7 October attacks in Israel, the Israeli government says.
None of the three has been named.
The Tanzanian authorities had previously confirmed that two of its citizens were missing. The BBC has spoken to the family of one of them, Joshua Mollel, who was an agriculture student on a kibbutz that was targeted.
Foreigners from 25 countries in all are being held by Hamas, Israel says.
They make up 135 of the 224 being held – the largest number, 54, being from Thailand.
They were taken when militants from Hamas – which Israel, the UK, US and other powers class as a terrorist organisation – crossed into Israel from Gaza killing at least 1,400 people.
Israel has since retaliated with air strikes on Gaza, which the Hamas-run health ministry says have killed almost 6,500 people.