Stalkers are preying on victims using tracking devices bought online for as little as £40.
The magnetic gadgets can be secretly attached to a car in seconds and are being advertised to suspicious partners.
Now a leading anti-stalking charity wants their sale restricted after they were used in murders and acid attacks.
Paladin National Stalking Advocacy Service’s Rachel Horman said more women would be killed unless the Government clamped down on their sale online.
Solicitor Ms Horman said: “These sites aid and abet stalking and murder. They have to be controlled so that only legitimate fitters can put them on vehicles.
“They are being advertised as products to assist you in stalking someone, not as anti-theft devices. They are actively encouraging people to do this.
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“When you look at the link between stalking and homicide it is really, really irresponsible.” Traders are advertising the devices to men who suspect their partner are having affairs.
One Bristol-based website says of its £49 device: “If you ever get the feeling that you’re being cheated on, the ideal thing would be to confront your partner. But not many people will be honest when they are cheating”.
Auction site eBay featured the gadget for as little as £40.
The rechargeable units relay the exact movements of the vehicle to the stalker via a simple app. A site based in Bradford, West Yorks, also offers cameras hidden in coffee cups and recording devices fitted in phone chargers and plugs.
Stuart Carless, 46, of Prestatyn, Denbighshire, was jailed for 14 months for stalking his ex wife in a campaign which included putting a tracker on his ex-wife’s car.
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A 40-year-old dad, who cannot be named for legal reasons, was jailed for 16 years after employing investigators to find his ex using tracking devices.
He got accomplices to throw acid in the face of his three-year-old son. The Sunday People is campaigning for a national stalking register to protect victims after a stalker boyfriend killed pregnant 17-year-old Jayden Parkinson.
Dawn Butler MP, Shadow Women & Equalities Secretary, said action needed to be taken.
She said: “These stories are appalling and deeply worrying for victims of stalking and abuse.”
