The M4 has been closed in both directions in Swindon as emergency services respond to reports of a person in distress on a bridge.
Police are currently blocking both the eastbound and westbound carriageways between junction 15 and junction 16 while officers deal with the ongoing incident.
The closures affect a key section of the motorway around Swindon and motorists are being urged to avoid the area.
At present, the entry slip roads have not been closed, although traffic is unable to continue along the affected section of motorway because of the police blocks.
Drivers should expect delays to build on the approaches to the closure and are advised to seek alternative routes.
Police are asking motorists to avoid the M4 in the Swindon area while the incident remains ongoing.
The closure is understood to be connected to concerns for the welfare of a person reported to be in distress on a bridge.
This is a developing incident and further updates are expected.