'Police pursuit' investigation after biker dies on M4
A motorcyclist has died after a police car attempted to pull him over for an alleged speeding offence on the M4.
The crash happened on the westbound exit slip road at junction 16 at about 19:30 GMT on Thursday.
The rider, who has not yet been identified, was pronounced dead at the scene, Wiltshire Police said.
The Independent Police Complaints Commission (IPCC) is investigating the incident and is appealing for witnesses to come forward.
An IPCC spokesman said: "It is understood at this stage that a Wiltshire Police marked car wanted to stop the motorcyclist for an alleged speeding offence."'Pursuit or not'
Rachel Cerfontyne, IPCC Commissioner, said: "This will be an independent investigation and will be carried out by IPCC investigators.
"We will be looking at whether the officers' actions were proportionate and whether this was a pursuit or not.
"We will also consider force policies and training."
Next of kin have been informed and an inquest is due to be opened on Tuesday.
The road was closed for several hours after the crash for an investigation.