GAZA (Reuters) - Israeli tank fire killed two Hamas gunmen in Gaza on Tuesday in a strike the Israeli military described as return fire for a shooting attack against its forces, an account disputed by the Palestinian Islamist group.

A relative of a Palestinian Hamas militant who was killed in Israeli tank shelling, reacts at a hospital in the northern Gaza Strip, August 7, 2018. REUTERS/Mohammed Salem

The two men killed in northern Beit Lahiya were Hamas snipers taking part in a live-fire exercise within a compound on Gazan territory, the group’s armed wing said in a statement. It deemed Israel’s shelling of them a “criminal act”.

In an earlier statement, the Israeli military said gunmen had fired on its soldiers from a Hamas post, which was shelled by a tank in response. There was no word of Israeli casualties.

The military released footage that it said was of the incident. One of the grainy black and white video clips shows two men in a watchtower, one appears to open fire as puffs of smoke burst in front of him. The video then cuts to separate footage of a shell hitting the post and an explosion.

Reuters was immediately unable to verify the footage.

U.N. and Egyptian-led efforts are under way to mediate a long-term truce between Israel and Hamas that would end a four-month surge of violence along the Israel-Gaza border.

At least 158 Palestinians have been killed in four months of weekly border protests and one Israeli soldier was shot dead by a Gaza sniper.

Israel says Hamas, which rules Gaza, is using the protests as cover to carry out cross-border attacks. Hamas denies this.

Palestinians militants have also fired rockets into Israel and the Israeli military has carried out dozens of air strikes in the enclave.

Israel has lost tracts of farmland and forest to fires started by kites and helium balloons laden with incendiary material which have caused fires in Israeli forests and farmlands and flown over the border by Palestinians in Gaza.