During the surprise assault on Israel by Palestinian militant group Hamas Saturday, gunmen opened fire on hundreds of young people during a dance music festival in the southern Israeli kibbutz of Re’im near the Gaza Strip, according to the Associated Press and multiple Israeli media outlets.

Witnesses told the Times of Israel that rocket fire was followed by gunshots fired into the crowd, as hundreds tried to flee.

“The music stopped and there was a rocket siren,” a young woman called Ortal told Israel’s Channel 12, according to Reuters. “Suddenly out of nowhere, they started shooting.”

Haaretz, one of Israel’s largest newspapers, described the scene as a “massacre” and a “battlefield,” and reported that terrorists on motorcycles drove into the crowd “opening fire.”