Police are warning shoppers in Preston not to fall for a scam after a man handed over £620 - for two bottles of water.
Officers were called after a man was approached by another man near Ringway and Friargate at about midday on Monday.
He was offered a deal to buy mobile phones, computers and tablets.
Police said he arranged to buy four iPhone 6s and a Macbook for about £620.
He withdrew the money and returned to pay the man. He was given a bag and on inspection found two bottles of water inside.
The man who claimed to sell the items is believed to have driven a grey car.
A police spokesman said: “If you are approached in the street by strangers offering mobile phones or computer equipment at low prices, it’s unlikely to be genuine.
“If it sounds too good to be true it probably is. We would urge shoppers to buy electronics from reputable dealers and be wary of such scams.”
Police issued a warning on Facebook about the scam.
The message said: “Shoppers please be aware, if you are approached in the street by strangers offering up to date mobile phones or computer equipment at unbelievable prices, it’s unlikely to be genuine.
“If it sounds too good to be true it probably is, that is, unless you want a very expensive bottle of tap water in a bag.
“We suggest you buy your electronics from reputable dealers.”
Anyone with information is asked to contact police on 101 quoting log number 0519 of November 23.