TEL AVIV — A young Israeli soldier, fresh from the front, bluntly recounts the orders from above. “They never said, ‘Leave no one alive,’ but they said, ‘Show no mercy,’ ” he explains. “The brigade commander said to kill as many as possible.”

Another recalls encountering Arabs on rooftops. “They’re civilians — should I kill them or not?” he asks himself. “I didn’t even think about it. Just kill! Kill everyone you see.” And a third makes it personal: “All of us — Avinoam, Zvika, Yitzhaki — we’re not murderers. In the war, we all became murderers.”

The wrenching, taped testimony is not from last summer’s bloody battle in the Gaza Strip but from the 1967 war, when Israel started out fighting Egypt, Jordan and Syria for its very survival and ended up seizing the West Bank, Gaza, the Sinai Peninsula and parts of the Golan Heights. As the International Criminal Court considers a war crimes investigation in the recent conflict, a new documentary film is showcasing previously unaired admissions of brutal behavior by an earlier generation.

Image Mor Loushy, director of "Censored Voices," a new film about the 1967 war.

The film, “Censored Voices,” premiered at the Sundance Film Festival on Saturday, the latest in a series of movies by leftist Israeli filmmakers who have won awards abroad by presenting harsh looks at their own society. Based on interviews that the military heavily edited at the time, it includes accounts of Israelis summarily executing prisoners and evacuating Arab villages in a manner that one fighter likened to the Nazis’ treatment of European Jews.