The M4 was closed in Swindon after a suspected drink driver fled his vehicle.
A member of the public took the man’s keys on Junction 16 at around 10.15am today (Thursday).
He then ran from the scene – towards to the motorway, sparking a full closure.
Police shut the M4 in both directions between Junctions 15 and 17 – in the vicinity of Junction 16.
Officers, including a dog unit, attended and carried out searches for the man – who another motorist believed was driving under the influence of alcohol.
Despite the urgent hunt, the suspect was not located. An investigation is ongoing.
In a statement, a spokesperson for Wiltshire Police said: “At around 10.15am, Thursday, morning, we received a report of a possible drink driver stopped on the M4 exit slip road at junction 16.
“A member of the public removed the keys from the ignition and the driver left the vehicle and walked towards the motorway.
“Traffic was subsequently stopped in both directions on the M4 for safety reasons and to allow for searches for the man to take place.
“He is yet to be found; however, we are confident he is not on the motorway and traffic has resumed. We have recovered the vehicle and our enquiries into the incident are ongoing.”