Scammers are making calls appear to come from genuine Avon and Somerset Police numbers as they try to persuade people to transfer money or reveal their banking details.

The force has received multiple reports of criminals impersonating officers, sometimes claiming a suspect has been arrested and the person's details have emerged during an investigation.

Some callers already know personal information about the people they contact, including nicknames. Others provide what appears to be a genuine crime reference number to make their story more convincing.

The fraudsters can disguise their caller ID using a technique known as number spoofing. Some people who called the displayed number back reached the force's control room, reinforcing their belief that the original call had been genuine.

The warning was published on 4 September. Police said reports had also come from people living outside the force area, suggesting the scammers were targeting people elsewhere while claiming to represent Avon and Somerset Police.

Amy Samotyj, a fraud protect officer at Avon and Somerset Police, said: "These fraudsters are highly convincing and often sound professional.

"They may claim an arrest has been made, provide what appears to be a genuine case reference number and tell you your personal details have been found as part of a police investigation.

"They may even know some information about you in advance."

She explained: "They're using these tactics to build trust and create a sense of urgency, which can make the calls seem genuine.

"It's important to remember that fraudsters can spoof telephone numbers, meaning the number displayed on your phone may appear to belong to a trusted organisation when it does not.

"Remember that Avon and Somerset Police will never ask you to move money, transfer funds to a 'safe account', withdraw cash, purchase gift cards, hand over bank cards or disclose banking security information as part of an investigation.

"If you receive a call of this nature, end the call and independently verify who has contacted you before taking any action."

Police are urging people to check a caller's identity independently rather than relying on a phone number, crime reference or collar number. A genuine officer will not object to someone ending a call to make those checks.

Anyone wishing to verify a police call can ring 101, ideally from a different phone, or allow time for the original line to clear before calling. Alternatively, they can visit a police station and speak to an officer.

Banking passwords, PINs and one-time passcodes should never be disclosed to callers. Anyone who has already transferred money should contact their bank immediately.

Suspected fraud can be reported to Report Fraud on 0300 123 2040. In an emergency, call 999.