This undated photo shows Austrian-born Alois Brunner, a Nazi lieutenant and senior aide to Adolf Eichmann. (Agence France-Presse)

Alois Brunner was the right-hand man to Adolf Eichmann during the Holocaust. But unlike his boss, Brunner evaded justice — and Nazi hunters — for decades, even as witnesses described encounters with the man in Syria. And now, Nazi-hunter Efraim Zuroff of the Simon Wiesenthal Center is certain that Brunner died at least four years ago, "unrepentant" in Damascus.

Brunner, who would be 102, was responsible for deporting more than 125,500 Jews in Europe to Nazi death camps during World War II. "The victims' families are a very large group and it's fair to say the people who suffered at his hands would have wanted him to be punished and would be disappointed," Zuroff told the Sunday Express this weekend. According to Zuroff, the Wiesenthal Center learned of Brunner's death from a "former German secret service agent who had served in the Middle East." The former agent told the center that "Brunner was dead and buried in Damascus" at least four years ago.

Zuroff described Brunner as "unrepentant" at the time of his death, adding, "He said himself his one regret was he did not kill more Jews." That's probably a reference to a 1987 phone interview Brunner gave to the Chicago Sun-Times. In it, he said, "the Jews deserved to die. I have no regrets. If I had the chance I would do it again." Brunner ran the Drancy transit camp outside Paris starting in 1943. During his tenure at the camp, there was a rapid deterioration in conditions for inmates, along with an increase in deportations to death camps, the New York Times writes.

Simon Wiesenthal, the Nazi hunter, described Brunner in his memoirs thus: "Among Third Reich criminals still alive, Alois Brunner is undoubtedly the worst. In my eyes, he was the worst ever. While Adolf Eichmann drew up the general staff plan for the extermination of the Jews, Alois Brunner implemented it.” Eichmann, widely considered a main organizer of the Nazi plan to exterminate Europe's Jewish population, was captured in 1960 in Argentina, tried in Israel and hanged.

In 2001, Brunner was sentenced in absentia to life in prison by a French court for arresting 345 orphans in Paris and sending them to the Auschwitz and Bergen-Belsen death camps, weeks before Paris's liberation. Just 61 of those children survived. During the symbolic trial, prosecutor Hervé Stephan said Brunner's "final arrests sprang from a desire to deport and to exterminate the very last Jewish children it was still possible to find on French soil."

So how did a notorious Nazi such as Brunner manage to evade justice for so long? The officer reportedly escaped from Europe to Syria in the 1950s and stayed put. Brunner reportedly used the fake name of Georg Fischer for years — something Brunner confirmed in the brief Sun-Times interview. Brunner has also said that his escape worked thanks to a mix-up with a similarly named ex-Nazi — Anton Brunner, who was hanged for war crimes. The mix-up was eventually untangled, but it gave Brunner time to flee and settle in Syria.

But little else about his story is confirmed.

Notably, that includes reports that Brunner lived in Syria under the protection of the Syrian government. Brunner reportedly helped President Hafez al-Assad develop torture tactics for the regime. However, Syria has never confirmed that Brunner played a role in the government or even that he lived there with the regime's knowledge. Zuroff described Brunner as "involved in the harsh treatment of the Jewish community of Syria" and being "an expert in terror and torture."

In 1991, former New York Times executive editor A.M. Rosenthal described Brunner's Damascus residence as something of an open secret: "For much of that time he has lived under the name of Georg Fisher at 7 Rue Haddad," Rosenthal wrote, "where foreigners have spoken with him and occasionally photographed him. In the past few years he even sat for a couple of interviews, in which he talked of his service to the Third Reich."

Rosenthal added that the Syrian government "quietly" rejected extradition requests from "France, Czechoslovakia, Austria and Germany." There are rumors that Brunner was very close to extradition to East Germany, just before the fall of the Berlin Wall. The fall reportedly halted the intended exchange.

But Brunner's time in Syria was not quiet. Yitzhak Hofi, a former Israeli spy chief who died this year, said the Mossad tried to kill Brunner in Syria in 1980 with a letter bomb. The attack took Brunner's eye and several of his fingers, but he survived. The bombing was one of two reported attempts on the former Nazi's life by Mossad — the spy agency also sent a pipe bomb to his house in 1961.

Brunner was last seen alive in 2001, at the Meridian Hotel in Damascus. According to Zuroff, the upheaval of Syria's civil war has made confirming the Nazi's death — or locating his burial site — impossible, at least for now. "No sane person is going to try to travel there to find out," Zuroff told the Sunday Express.