Just as IDF Chief of General Staff Lt.-Gen. Gabi Ashkenazi spoke of the quiet in the South being a testament to the success of Operation Cast Lead, tensions threatened to flare once against on the Gaza front, with Palestinians firing a Kassam rocket into Israel after the IDF killed a suspected terrorist near the border fence. The rocket landed in an open area in the Sdot Negev region, causing no casualties or damage. IDF soldiers shot the suspected terrorist dead early Friday morning, thwarting an apparent bomb plot near the Gaza fence. The army said that Nahal Brigade soldiers spotted a Palestinian terror cell that appeared to be planting explosive devices south of the Karni crossing. The soldiers crossed the border and fired at the suspects, said the IDF. None of the troops were wounded. The army said one man was killed, another was taken for medical treatment in Israel and four others were taken for questioning. A Palestinian hospital official said the men were civilians hunting birds. He spoke on condition of anonymity because he was not authorized to release the information. The IDF said it was investigating if the men actually planted a bomb and if they were armed. Speaking to high school students in Beersheba, Ashkenazi maintained that the IDF was the most moral army in the world, while conceding that mistakes were sometimes made. "We will continue to investigate. We have found mistakes and failures, because in the heat of the battle they happen. We are learning lessons and we will correct our mistakes," he said concerning last winter's Operation Cast Lead and the Goldstone Commission's scathing report. "The report needs to be responded to in order to explain the justification for the war and that the next war will be fought in the same way. We shouldn't reward terror. We are investigating all the necessary incidents, but we do this after every war, irrespective of reports." Ashkenazi said that the operation had served its purpose, since southern Israel was quiet for the first time in eight years. He went on to blast Hamas for operating in civilian areas. "We hit [innocent] people, but Hamas intentionally operates in built-up areas, and we need to protect ourselves when, for example, we see a terror cell setting up a Grad missile to be fired at Beersheba, and that's exactly what we did," he said. If Hamas continues to launch rockets at Israel, stressed Ashkenazi, Israel would have no choice but to conduct another operation in Gaza. "We also check Palestinian complaints, something no other army does, and sometimes we're not proud of the results," he continued. On Wednesday, The Jerusalem Post reported that the Military Police had launched a new criminal investigation into allegations that soldiers committed war crimes during Operation Cast Lead, and that human rights organization B'tselem would to help gather testimony from Gaza.