Lincolnshire Police are warning people that criminals are posing as police officers to commit fraud.
Across the county, criminals are impersonating officers and calling people, asking victims to give them money or provide bank details.
In some cases, the frauds have asked victims to buy expensive goods like jewellery for collection.
Lincolnshire Police are now issuing a warning to the public, saying that a police officer would never ask someone to give them money.
Nicholas Bates from the crime prevention team said: “We have recently seen an increase in reports of these calls, which are being made to people across Lincolnshire.
“Often it is the elderly who are targeted. If you have a relative or friend who you think could be vulnerable, please speak to them and make them aware of this fraud.”
The force are urging anyone who receives a similar call to hang up the phone and call them on 101.