Deadly car seats that can kill a child at 30mph and fail all UK safety standards have been found in Surrey, after being imported from China.

A Surrey County Council investigation uncovered a market in the killer car seats after following up on a complaint about a sale.

Crash testing by Britax, a child travel safety company, shows the seat ripping apart on impact at 30mph the the dummy, the size of a three-year-old-child, catapulted through the front windscreen.

So far about a dozen seats have been taken off the market, with the council working with eBay and Amazon to remove more than 100 more.

Helyn Clack, Surrey County Council's cabinet member for community services, said: "Our priority is protecting Surrey families from these killer car seats which tear apart so easily.

"We'll continue to track and seize these deadly car seats, but our operation in England is just the tip of the iceberg as global online sales are our biggest problem."

Telltale signs include the illegal seats have no maker's label, include no details of the manufacturer on the car seat, have vague pictorial instructions and are made of flimsy material.

Mark Bennett, Britax car seat safety expert, said: "We would always recommend that prior to purchasing a car seat you visit your local retailer to discuss in detail your family’s individual needs and have the car seat installed properly by in-store trained staff."

Some foreign websites are ignoring UK laws on safety and still selling the seats online, the Department for Business, Innovation and Skills has been alerted to the problem.

Mr Bennett said: "If in any doubt about the safety or origin of your child’s car seat we would recommend you seek expert advice from the relevant retailer, manufacturer or your local road safety officer to ensure your most precious cargo is protected."

To report a car seat, contact Surrey County Council trading standards department on 03454 040506 (9am-5pm weekdays).