MOBILE phone owners are being urged by police to make a note of their phone's IMEI number.

The 15-digit number is unique to each phone.

It remains even if the SIM card is changed and can be used to help identify it if the phone is stolen or lost.

People who call police to report a phone theft are asked for the IMEI number.

Owners can find the number by keying in *#006# or checking under the battery.

They can register their phone at immobilise.com or through its information line on 08701 123123.

Owners can also use an ultraviolet pen to mark their mobile phone with their postcode and house number.

They should call their service provider if their phone is lost or stolen and it will block the phone to all networks, making it useless.