As people take advantage of Black Friday and Cyber Monday sales, the FBI has warned those purchasing smart TVs that some could be used as a window into your home by crooks.

According to the intelligence agency's Portland, Oregon, bureau, which issued a reminder last week, the useful features of a smart TV, such as internet connection, microphones and cameras, are also means that hackers can use to gain access to your home.

“Beyond the risk that your TV manufacturer and app developers may be listening and watching you, that television can also be a gateway for hackers to come into your home,” the FBI wrote. "A bad cyber actor may not be able to access your locked-down computer directly, but it is possible that your unsecured TV can give him or her an easy way in the backdoor through your router."

Hacking can range from the ability to “change channels, play with the volume, and show your kids inappropriate videos,” to using the TV’s camera and microphone to “cyber-stalk,” the bureau warned.

Fortunately, there are ways to enjoy the benefits of a smart TV while protecting yourself.

The 10 best smart TVs Show all 10 1 /10 The 10 best smart TVs The 10 best smart TVs {1} PANASONIC P50GT30B 50IN PLASMA

The only plasma on test, the Viera Connect system is a great looking interface with lots on offer including games, Facebook, music and video services, with catch-up TV on its way. The best 3D picture here.

£1,384.90, amazon.co.uk The 10 best smart TVs 2. Samsung UE46D8000 46in LCD

Best Buy: This exceptional TV comes with the Samsung Smart Hub portal of three dozen apps including iPlayer and has exceptional picture quality. The TV also has the best styling on test.

Price: £1,849, johnlewis.com The 10 best smart TVs 3. Panasonic L37DT30B 37in LCD

Like the Panasonic P50GT30B, this model has Viera Connect as its good-looking smart interface, though neither has wi-fi built in - you need to connect it to your router by cable or buy a dongle. The set has an HD Freeview tuner.

Price: £944.90, amazon.co.uk The 10 best smart TVs 4. Samsung UE40D7000 LCD

Samsung's D7000 series has an internet browser and a wide range of apps from games to LoveFilm, YouTube to Skype. The TV has wi-fi built in so it can connect easily to the internet.

Price: £1,418, johnlewis.com The 10 best smart TVs 5. Loewe 3D 46in LCD

Best Luxury Buy: The Loewe streams from the internet or a home network and has wi-fi and a 500GB hard disk built in. You can even stream content to another Loewe (handy if you want to go to bed mid-movie).

Price from £4,100, loewe-uk.com The 10 best smart TVs 6. Sony Bravia KDL-40EX523 40in LCD

This super-slim Bravia has the capability for making Skype calls with an optional add-on. It also has access to internet video.

Price: £849, sony.co.uk The 10 best smart TVs 7. Philips 40PFL7605, 40in LCD TV

This model still has the strong Philips Net TV smartness, though no wi-fi (£50 dongle available). It's also available in a slightly bigger version with a design-your-own colour and finish.

Price from £750, philips.co.uk The 10 best smart TVs 8. Sony Bravia KDL LCD

Best Budget Buy: This good value 32-inch TV has Freeview HD, and Bravia internet TV which includes BBC iPlayer, access to LoveFilm and a remote control app for your smartphone.

Price: £499, sony.co.uk The 10 best smart TVs 9. LG 47LW550T, 47in LCD

LG's smart TVs come with their own apps, just as Samsung's do. There are games, Facebook, Google Maps, iPlayer, movie trailers and extra channels.

Price: £1,399.99, comet.co.uk The 10 best smart TVs 9. Philips 21X9 Platinum, 58in LCD TV

The stand-out feature here is the amazing shape, which makes it perfect for watching films. But this is a smart TV, too, with superb net surfing and built-in wi-fi.

Price: £3,999, philips.co.uk

If you have a smart TV, the first thing you should do is “know exactly what features your TV has and how to control those features,” according to the FBI, which is easily done by doing a basic internet search with your model number and key words such as “camera” or “microphone”.

Consumers should also not depend on default security settings, the FBI advises, and should know how to turn off microphones, cameras and collection of personal information if possible. If the TV model does not allow you to turn off the camera, the FBI suggests placing black tape over it - or considering whether you are "willing to take the risk of buying that model or using that service".

The FBI also recommends checking the “manufacturer’s ability to update your device with security patches” and checking the privacy policy for the TV manufacturer and streaming services you use to “confirm what data they collect, how they store that data, and what they do with it”.