Beware the electrical bargains that could catch fire, cause electric shocks or melt into your carpet

Nearly three quarters of cheap electrical devices bought online are unsafe, research shows.

The tests on dozens of USB chargers, travel adaptors and power banks showed many had potentially lethal faults.

Experts at consumer group Which? looked at unbranded or unrecognised brands sold through Amazon Marketplace, eBay, Wish and AliExpress. They found products so poorly designed they could cause electric shocks and start fires.

Eight of 12 USB chargers for use with Apple iPhones were dangerous as were 11 of 12 USB travel adaptors. ‘Online marketplaces that list cheap and unsafe electrical products sold by unknown brands are putting people at risk,’ said Natalie Hitchins, head of home products and services for Which?

‘These products might be cheap but our testing shows they have the potential to cause serious damage or injury, including electric shocks and fires.

‘Online marketplaces need to take greater responsibility for the products that are sold on their sites – while the product safety authorities must do much more to identify unsafe products and keep them out of homes.’

Four of nine power banks failed tests and one was put together so poorly that it started to smoke and melt. Overall nearly three quarters of the products purchased by Which? failed electrical tests.

Home Office data shows that fires caused by such products have nearly quadrupled in England since 2011.

All four online marketplaces said they would remove listings for unsafe items.

The products tested were all sold as new and were either unbranded or were a brand that the testers did not recognise.

Seven of the 12 travel adaptors failed electrical strength tests.