Two police officers were among three people injured in a five-car motorway crash in Sussex.
The collision happened on the M23 near Patcham just after 11am on Saturday.
Officers had been responding to a black Audi which was clocked speeding on the northbound carriageway by automated number plate recognition (ANPR) cameras.
Five cars collided, including two police cars which were not part of the pursuit, Sussex Police said.
No details were given on the conditions of any of the three people injured.
A 23-year-old woman was later arrested on suspicion of driving under the influence of drugs, driving without a licence, and driving without insurance.
Anyone who saw the crash or who has dashcam footage is asked to email collision.appeal@sussex.police.uk or call 101 quoting 223.
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