Security researchers warn it is possible to take control of some cars, via flaws in the smartphone apps linked to their "smart" alarms.

The researchers showed BBC Click's Dan Simmons how the flaws could be used to hijack a high-value vehicle.

One of the companies behind the products, Directed, told the BBC it is "committed to providing safe and secure products but no system can be 100% safe".

Russia-based Pandora Alarms, which also sells its products in the UK, said: "We have made changes to the code and upgraded security."