Israel's chief Nazi hunter has arrived in southern Chile to step up the hunt for the Nazi fugitive Aribert Heim.
Heim - known as Dr Death - is believed to be in the Patagonian regions of either Chile or Argentina.
Efraim Zuroff, of the Simon Wiesenthal Centre, will spend two days in Chilean Patagonia before crossing to Argentina.
Heim tortured and killed prisoners in Mauthausen concentration camp in World War II, but fled Germany in 1962 before authorities were able to arrest him.
Chilean and Argentinean newspapers have published pictures of Heim in 1950, 1959 and how he might look now. These are also displayed on posters advertising the search.
"In the last few days we've received information from two different sources, both relating to Chile, which we think have very good potential," the director of Israel's Simon Wiesenthal Centre, Mr Zuroff, said.
"The reason we are going [to Patagonia]... is of course the fact that Heim's daughter lives in Puerto Montt, and we think there is a strong likelihood that he might be in that area or in the area between Puerto Montt and Bariloche [Argentina]."
The Simon Wiesenthal Centre, along with the German and Austrian governments, has offered $495,000 (315,000 euros; £250,000) for information leading to Heim's arrest.
Although he would now be 94, they believe Heim is still alive because his family has yet to claim around $1.6m sitting in a German bank account in his name, says the BBC's Gideon Long in Santiago.
In order to make the claim, his family would have to prove he is dead.
The search for Heim is part of Operation Last Chance, a final bid to bring Nazi war criminals to justice more than 60 years after the end of WWII.
Heim kept meticulous notes of his activities at Mauthausen.
According to Holocaust survivors, he performed operations and amputations without anaesthetic to see how much pain his victims could endure.
Injecting victims straight into the heart with petrol, water or poison were said to have been his favoured method at Mauthausen.
"His crimes are fully documented by himself, because he kept a log of the operations that he carried out," Mr Zuroff said.
"He tortured many inmates before he killed them at Mauthausen, and he used body parts of the people he killed as decorations."
After the war, Heim was detained by US forces, but later disappeared.
He practised medicine in the German town of Baden-Baden until 1962, when he fled the country after being tipped off that the authorities were about to prosecute him.