The elderly man had €28,000 in cash and was on his way to hand over the money, thinking that he was helping out a family member in need.
The taxi driver heard him speaking on his mobile phone to someone, realised he was being scammed, and called the police.
When they arrived at their destination of Weiden am See the police were there as well and arrested a 28-year-old woman after the pensioner had handed over his cash to her.
Police said the woman was a courier working for an international gang that is well known for such scams. Earlier this week they had already tried to get a total of €158,000 from a 56-year-old-man and an 87-year-old woman in Neusiedl am See, by calling them on the phone and pretending to be a younger relative in urgent need of financial help.
"The 85-year-old man was called by one of the fraudsters several times during the taxi journey. The taxi driver became suspicious and called the police station at Neusiedl am See," police spokesman Wolfgang Bachkönig said.
The pensioner got his money back after the woman had been arrested, and she is being held in police custody. Police said she has confessed to her part in the fraud but has not given them any more details about the gang's activities.
Police recommend that people help minimize their chances of falling victim to one of these elaborate scams by checking with other family members if they do get a call, asking questions that only the “real” family member would know the answers to, or calling local police departments.