A warning has been issued over a scam offering discounted travel across the Mersey Gateway bridge.

Cheshire Police have been alerted over the fake website and phone number, with motorists urged to be vigilant.

The new bridge, which links Runcorn and Widnes and will be used regularly by Frodsham and Helsby residents, is due to open this autumn.

Discounts on tolls are available via a website and call centre run by bridge operators Merseyflow, who have warned that motorists should only use these official channels and no others.

Anthony Alicastro, chief executive of Merseyflow, said: "We know that there are some criminals trying to set up fake numbers and websites to con people.

“We're watching them and have already informed the police and will take whatever action we can to shut them down.

“We'd hate anyone to fall victim to these criminals.”

Work started on the Mersey Gateway project in May 2014 and the six-lane bridge is close to completion. It will replace the ageing Silver Jubilee Bridge, which will close to motorists for a time for maintenance work before being reopened as a toll bridge.

Travel over the bridges will be free for Halton residents, but efforts by politicians to get this offer extended to people in Cheshire West and Chester failed.

The majority of drivers will be charged £2 per journey – this is for cars and small vans – but you can register for small discounts with Merseyflow.

Instead of toll booths, Merseyflow will use a number plate recognition system which will ensure traffic will run as smoothly as possible.

You will be able to drive over without registering but, if you do, you will subsequently have to go online and pay the full unregistered toll cost. Those who do not pay in time will be hit with a £40 fine.

More than 17,000 vehicles have been registered with Merseyflow so far.

The official website address is www.merseyflow.co.uk and the official call centre number is 01928 878 878.

If you think you have been caught out by a scam, or have any concerns about other fraudulent activity, contact the police on 0300 123 2040 to report the crime.