Residents have been urged to ensure they only use pre-booked taxis and private hire vehicles.

The warning from Wiltshire Police comes a week after an alleged sexual assault outside an Old Town nightclub, in which the police said the suspect may have posed as a taxi driver.

Taking to Facebook on Friday afternoon, A/Supt Al Lumley warned residents only to use pre-booked taxis, warning that using unbooked vehicles may mean companies have no record of their journey and they could even be uninsured if there is a crash.

She said: “We want everyone to travel around our town safely and in the knowledge they are using licensed, regulated companies when jumping into taxis or minicabs.

“To access most of these, you will need to book in advance, however, some are unlicensed and tend to look for customers on the streets and usually at night.

“Our advice is simple; never get into an unbooked minicab because there might not be any record of your journey or driver.

“They may also be uninsured in the event of an accident.

“Booking your minicab in advance means your trip will be carried out by a licensed, insured driver in a licensed, insured vehicle.

“A record of your journey, driver and vehicle will also be logged so that, in the event of any issues, the driver can be traced.

“Another good tip is to make a note of or take a picture of the vehicle's number plate and licence number.”

The advice comes almost a week after a woman was allegedly sexually assaulted outside Tree nightclub in Old Town.

Police on patrol in Hoopers Place were flagged down in the early hours of Sunday, September 4.

Later on in the day, DCI Nick Mawson said: “This is an extremely concerning incident involving a man who also encouraged the woman to get in his car, suggesting he could be a taxi driver.”

Two men have since been charged in connection with the incident – they both deny all charges.

Foreign student Nikhil Chopra, 20, of Scarborough Road in Walsall, and asylum seeker Aryan Choudhary, 21, of no fixed abode both face charges of sexually assaulting the woman outside the nightclub.

Chopra was also charged with indecent exposure.

Mark Glendenning, Choudhary’s defence solicitor, told the court: “He says that he has no involvement in this incident at all other than to speak to this young lady and have his photo taken with her voluntarily."

They were both remanded in custody and will appear at Swindon Crown Court on October 6.