Two Hamas members were killed and three are missing after a tunnel in the Gaza Strip collapsed, the Islamist group's military wing said Thursday.
"The Al-Qassam Brigades hail the fighters Ismail Abdul Kareem and Rami Muneer from Shejaiya, who died following the collapse of a resistance tunnel," it said.
A source close to Qassam said five militants were in the tunnel when it collapsed and efforts were continuing to find and rescue the other three.
Over the years, the Hamas rulers of Gaza have built a labyrinth of tunnels, including those crossing under the border with Israel, for use in any renewed conflict.
Israel and Palestinians in Gaza have fought three wars since 2008 and the territory has been under an Israeli blockade for a decade.
Attack tunnels were a key weapon for Hamas during the last conflict in 2014, with a number of surprise attacks inside Israeli territory.
The group also built a vast network of tunnels under the border with Egypt to smuggle weapons and goods of all kinds but those have been severely disrupted by Cairo's establishment of a no-man's land along the frontier.
In recent months, at least 23 Gazans have died in tunnel incidents, most of them Hamas militants.
*The story was edited by Ahram Online.