A scam artist has been arrested after his target, a 95-year-old woman in Rahlstedt, Hamburg, alerted authorities when the fraudster attempted to convince her to hand over thousands of dollars, Hamburg police reported.

The pensioner received a phone call on Tuesday from a woman who pretended to be a friend, and said she was in hospital due to the coronavirus and urgently needed € 30,000 ($35,600) for a ventilator.

The elderly woman quickly recognized it was a fraud attempt, played along, and said she would retrieve €20,000 from the bank.

Unnoticed by the caller, the pensioner asked her caretaker to alert the police, who then arrived at the pensioner's home, listened in the phone call and guided her.

The scammer asked her for even more money, and she promised a further €11,000. The call then ended, only to be followed by a series of more fraudsters phoning in under numerous disguises.

The scam has prompted Hamburg police to issue a warning regarding telephone fraud, a common occurrence in Germany.

"Unfortunately, cases like this keep happening. The perpetrators have been trained and are extremely skillful. Again and again there are massive, sometimes existential damages."

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Fake policeman, medic and bank employee

Shortly after the first scam call, a man pretending to be a policeman phoned the pensioner, alleging that he was carrying out a control call, asking if any police were present in her building.

"Schneider" told the pensioner  that he had received an alert from her bank about a major cash withdrawal, and said a tax offense investigation might have to be conducted. 

Next, an alleged bank employee phoned, asking the 95-year-old to confirm whether she had made a large transfer.

The original caller then phoned the elderly lady once more, and said a hospital "employee" would come to her home to collect the money. She told the pensioner to hand over the money in an envelope.

During this time, special investigators on standby noticed a man step out of a taxi and walk towards the pensioner's home.

As investigators watched on, the elderly lady handed over an envelope to the collector.

Officials then temporarily arrested the man, a 47-year-old Slovak. Further investigations are ongoing.

"Be suspicious of people pretending to be relatives or acquaintances on the phone…Do not allow yourself to be pressured even in the event of an alleged emergency…Hang up at the slightest doubt!" Hamburg police said in a statement.