Officers in Wiltshire say they've had reports of it happening between Junctions 19 and 15.
Swindon attack E-fit released
Detectives in Swindon looking into an assault on a young woman at Nythe have released a an E-fit (pictured) of her attacker.
Officers were called out to Kimmeridge Close at about 11.40am on Wednesday 4 July.
She was left shaken by the assault and with a small cut to the stomach and reddening to the neck and face.
She described her attacker as white, about 5ft 7in tall, of slim build, in his mid to late 40s, with very bushy dark brown eyebrows, dark eyes, and with a long nose with a distinctive lump on the bridge.
He is said to have stained teeth and appears to be clean shaven. He was wearing a black woolly hat and a black shiny jacket.
Detective Constable Megan Kenzie said:
“This attack happened late morning in broad daylight. The victim describes shouting out at the top of her voice so we are appealing for any witnesses who may have seen this attack or who think they can identify the man involved.”
Anyone with information is asked to contact Det Con James Newbery at Swindon CID on 101 ext 760 627 .
Police say Jack Parfitt hasn't been seen for nine days.
Advice to keep cool as the temperature rises
West terminal to be extended to improve security area
Recently Played Tracks
Discover this season's unmissable TV like Yonderland, and win Sky TV free for a year
Get a 200% Welcome Bonus. Deposit £10, get £30 to play! T&C's apply.
Find your local four day weather report here.
What's happening on the roads where you are?
Make Heart the soundtrack to your day and you could be a winner with great prizes up for grabs throughout the day.
Find out more about some of the companies advertising on Heart.
Get some great ideas on how to advertise your business on radio, online and on mobile.