An Austrian accused of sending more than 125,000 Jews to their deaths has become a leading target of American Nazi hunters just as the United States has accelerated dealings with Syria, the country that apparently harbors him.

Alois Brunner, 73, is considered responsible for decimating Jewish communities in Austria, Greece and France during World War II. Interest in the search for him has been heightened by the recent discovery in Brazil of the remains of Nazi war criminal Josef Mengele, and by Syria's assistance in freeing American hostages held until Sunday in Beirut.

Rabbi Marvin Hier, dean of the Simon Wiesenthal Center here, said his organization plans to announce rewards soon for information leading to the capture of 10 prominent war criminals. Hier said Brunner would be second on that list after Nazi Gestapo chief Heinrich Mueller, whose whereabouts are unknown.

Brunner has gone almost unnoticed since finding refuge in the Arab world in the late 1940s, according to Mary Felstiner, a history professor at San Francisco State University and a visiting scholar at Stanford University.

Felstiner is about to issue an extensive report on Brunner, who is living under the name Georg Fischer and who survived a 1961 letter-bomb attack that took an eye and an arm. She said there are reports that he not only has been protected by the Syrian government but has worked with the Syrian secret police and may have helped test torture equipment.

Felstiner said she believes Brunner may have been particularly vicious toward Jews to divert attention from his physical characteristics -- the hook nose, thick lips and black, kinky hair often found at the time in anti-Semitic caricatures of Jews.

Brunner, a member of the Nazi SS, became particularly adept at balancing threats against favors to persuade Jewish community leaders to help round up people for what turned out to be trips to death camps, Felstiner said.

Brunner was head of the Vienna central office that by 1943 had deported 48,000 Austrian Jews to concentration camps in Poland. He turned the Kultusgemeinde, the main Jewish community organization, into "a funnel for the central office," Felstiner said: Jewish leaders would help him in exchange for protection for such people as veterans, elderly and invalids -- and themselves.

Once Brunner had most of the people he wanted, she said, he would revoke the protections and take the rest.

In Salonika, Greece, where he depopulated one of the oldest Jewish communities in Europe, Brunner lived in a magnificent mansion with specially installed torture chambers in the basement. One witness said Brunner "flogged his victims with a horsewhip made of thin leather thongs threaded with iron wire. Then he terrorized them with a pistol which he aimed against their necks, foreheads or temples."

Witnesses said he was obsessed with exterminating Jewish children and women of childbearing age to prevent the next generation from taking revenge for what he had done. Using a route through Austria that remains unclear, he escaped capture after the war.

Felstiner said she hopes that the same international interest that led investigators to Mengele's remains will be focused on Brunner.