JERUSALEM (JTA) — A Hamas military exercise set off Code Red alerts in southern Israeli communities and caused the Iron Dome anti-missile system to misfire.

At least 10 missile alerts were activated in Sderot and the regional councils of Hof Ashkelon and Shaar HaNegev on Sunday night. In addition, the Iron Dome anti-missile system activated, firing unnecessary missile interceptors, the Israel Defense Forces said later on Sunday night.

The alerts and Iron Dome were triggered by a live-fire exercise in Gaza by the Izz ad-Din al-Qassam Brigades, the military wing of Hamas, the terror group that controls the Gaza Strip. The exercise started on Sunday morning and was scheduled to end on Monday morning.

The IDF retaliated for the believed missile attack, striking two Hamas positions in the northern Gaza Strip using tank fire.

“No salvo was fired at territory in the State of Israel. The situation in the Gaza region is usual. The interceptions by the Iron Dome system were activated because of the firing of bullets from the strip. Nothing fell in Israeli territory. It is being checked whether mortars or rockets were even fired at all,” said a statement issued by the IDF late Sunday night.

It was the first time since Hamas took over Gaza in 2007 that a military exercise in Gaza was announced in advance, with warnings about live fire and the sounds of explosions, Haaretz reported.