A Hamas operative was killed as a tunnel collapsed in the southern Gaza Strip on Friday, his Islamist movement which rules the Palestinian territory said.

It said Yussef al-Agha died in Khan Yunis in the collapse of a “resistance tunnel,” the type dug for attacks against Israel.

Last year, 22 members of Hamas’s armed wing were killed “preparing equipment,” the majority in a string of tunnel collapses, the terror group said last month.

Gaza terrorists have dug dozens of tunnels, many coming under the border into Israel, to launch attacks against the Jewish state; Israel destroyed many of them during the devastating 2014 war with Hamas. It says Hamas has since been rebuilding the network, and Hamas has bragged about doing so.

Israel and Hamas have fought three wars since 2008 and Gaza has been under an Israeli blockade for a decade, imposed by Israel and Egypt to try to prevent it importing weaponry.

“Attack tunnels” were a key weapon for Hamas during the last conflict in 2014, with a number of raids inside Israeli territory.

Egypt, which shares a border with Gaza, has also destroyed tunnels Palestinians use to smuggle commercial goods, cash, people and weapons.

Several Palestinians were also killed last year in tunnel collapses on southern Gaza’s border with Egypt.