Police are issuing the warning following an increase in the number of thefts from vehicles parked in shopping centres including Silverlink and Royal Quays outlets.

Detective Inspector Barry Worthen said: "Although the numbers of reported incidents are very small we don't want them to creep up.

"Especially now the nicer weather is on the way, it's all too easy to park up and leave a window open – our advice is don't.

"Make sure your car is left fully secure with all doors and windows locked shut.

"It only takes seconds for an opportunist thief to reach in and steal your valuables. Don't make it easy for them.

"We know that thieves like small valuable items which are easy to carry off, and often target portable sat nav devices which are left on show, so make sure you remove them from sight and the tell tale fixings which tip off a thief that a sat nav is used."

Simple crime prevention advice includes:

• Think about where you park, use well lit places or secure car parks if possible


• remove portable sat nav systems and their holder when you leave your car and don't leave any tell tale sucker marks visible on the dashboard


• don't leave mobile phones, iPods or other valuables on display


• if you need to store any shopping in your car temporarily, keep it out of sight in the boot


• remove detachable radios and CD players


• use a security lock or other deterrent if possible


• never leave car documents or spare keys inside the car


• when away from home look for a parking space in a well lit, busy place. At home, park in a garage if you have one

report any suspicious activity to the police.