M4 junction 16: Police search for driver causes chaos
Police received reports of a man who stopped their vehicle on the exit slip road at junction 16 at around 10.15am. Officers say a "member of the public" took the keys from the vehicle before the driver fled and walked towards the motorway. Police brought traffic to a standstill for safety reasons while they searched for the man and recovered his vehicle.
On Thursday afternoon, officers added that the search was ongoing, but they were "confident" the man was no longer on the motorway, and traffic had resumed. 
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[1] 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." Traffic was brought to a standstill in the wake of the incident, with the AA Travel News' interactive travel map showing heavy traffic building on the M4.
A note highlighting the incident read: "All lanes stopped and stationary traffic due to police incident on M4 both ways at J16 A3102 Swindon Road (Swindon West)." Footage from traffic cameras showed police sweeping the National Highways, the organisation that manages the M4, took to X to announce that traffic had been stopped for the 'police led incident'.
They added that there were delays of 45 minutes and 2 miles of congestion.
At around 11.30am, National Highways confirmed that all lanes on the M4 had reopened and traffic had begun moving, although persistent delays were likely.
As of 2pm, travel maps showed traffic running smoothly along the M4 once again.