An ice-cream van was hijacked at knifepoint by a gang of robbers after the driver pulled over thinking they were customers.
The seller assumed the men had wanted to buy ice cream
The three robbers who were travelling in a Ford Escort stole the van after they forced it to pull over in a country lane near Westbourne in West Sussex.
Police said when the van was at a standstill, two of the men approached it and the seller, who had just finished a round nearby, opened the hatch assuming they wanted to buy ice-cream.
But while he was talking to them, the third man burst into the back of the van and threatened him with a knife.
The robbers may have gone on to empty the van of its ice-cream or even gone on to sell it
All three robbers then drove off in the van leaving the vendor to walk a mile to get help.
Police said the ice-cream seller was unhurt but shocked by the incident which happened on Sunday afternoon.
A spokesman for the Sussex force said: "The robbers may have gone on to empty the van of its ice-cream or even gone on to sell it."
So far the van had not been located but police said there had been one unconfirmed sighting of the vehicle on Monday morning.
Detectives want to speak to anyone who may have seen the van, which is described as green and yellow with a sign saying "Verrossi", to come forward.