ROME, April 15 (JTA) — Former Nazi SS Capt. Erich Priebke went on trial this week to face for a second time war crimes charges related to Italy’s worst World War II atrocity. The retrial opened Monday, when the military court ruled that another ex-Nazi, former SS Maj. Karl Hass, would be tried jointly with the 83-year-old Priebke on similar charges. Both face charges in the March 1944 mass execution of 335 men and boys in the Ardeatine Caves south of Rome. The Nazis ordered the massacre in reprisal for an Italian partisan attack that killed 33 German soldiers. More than 70 Jews were among the massacre victims. Dozens of relatives of victims or their representatives were in attendance when the trial opened in a high-security courtroom at Rebibbia Prison on the outskirts of Rome. “All we want is justice,” said one. “This is the last opportunity for Italy to face up to that period of its past,” said Shimon Samuels of the Simon Wiesenthal Center, who has followed the case closely from the start. Priebke, who is being held under house arrest at a monastery near Rome, attended the session briefly, but told the court that he probably would not attend further hearings. “I am here today out of respect for the tribunal,” he said. “But I fear it will not be this way in the future because I am not well. I am available for whatever may be needed.” Hass, 84, did not attend the opening session. His lawyer said he would not attend the trial because of health problems. He is being held under house arrest at an old-age home near Rome. The first Priebke trial began last May, two years after the former Nazi was discovered living in the Argentine Andes town of Bariloche, where he had settled after fleeing from a POW camp after World War II. In November 1995, he was extradited to Italy after 18 months of legal wrangling. Priebke, who has admitted taking part in the Ardeatine Caves massacre, was found guilty by a military court in August, but the court ordered him freed due to extenuating circumstances and what it said was an expired statute of limitations. That verdict triggered protests by family members of the victims, who barricaded the courthouse for eight hours until Priebke was rearrested, pending an extradition request from Germany. In October, the verdict was annulled by an appeals court, which ruled that the judges had been openly biased in Priebke’s favor, and a new trial was ordered. Hass, who also has admitted taking part in the massacre, was a witness at the original Priebke trial. He tried to escape testimony by jumping from his hotel balcony, but he broke his hip and eventually testified from a hospital bed. Last month, Italy’s national pension office has revealed that Hass, who has lived in Italy for decades, receives state pensions from both Italy and Germany. The office confirmed at the time that Hass draws nearly $120 a month from Italy and about $530 a month from Germany. Both men defend their role in the Ardeatine Caves massacre by saying that they were just following orders and would have been killed themselves had they disobeyed.