Hamas’s deputy political commander, Marwan Issa, was “eliminated” in a military strike earlier this month, Israel has said.
If the intelligence is correct, he would be the highest-ranking Hamas leader to have been killed in Gaza since the start of the current conflict between Israel and Hamas in October.
Fighter jets struck an underground compound in central Gaza between 9 and 10 March.
Another Hamas commander, Aziz Abu Tamaa, was believed to be with Issa.
The Israel Defence Forces said it had confirmed preliminary reports.
“We have checked all the intelligence,” Rear Admiral Daniel Hagari said.
“Marwan Issa was eliminated in the strike we carried out around two weeks ago.”
Issa was known as “shadow man” for his ability to evade Israeli forces and had reportedly been hiding underground.
Born in 1965, he was thought to be one of those behind the Hamas attacks in Israel on 7 October.
About 1,200 people were killed and hundreds more taken hostage.
Others on Israel’s most-wanted list include Mohammed Deif, the head of Hamas’s military wing, and Hamas’s leader in Gaza, Yahya Sinwar.
Both are believed to be in Gaza.
Sinwar spent more than two decades in Israeli prisons before being released with more than 1,000 other Palestinian prisoners in exchange for a captive Israeli soldier in 2011.