(CNN) A California cab driver knew something sounded fishy when his elderly passenger said she needed a ride to the bank to withdraw $25,000.

Rajbir Singh picked up a 92-year-old woman in Roseville, California, two weeks ago. When he started chatting with her, Singh said she told him she was about to withdraw the money to settle a debt with the IRS.

He pleaded with the woman to reconsider, saying he thought this could be a scam. Singh even detoured to a police station to help convince his passenger not to withdraw her money.

"I am an honest guy, and these are old people. They need help," Singh, the owner of Roseville Cab , told CNN on Thursday. "It just made sense."

As Singh talked to the woman, she told him that someone had called her and asked for the money. When he asked if it was a family member, the woman grew silent.

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