The 41-year-old man was arrested in a pub in Frome, Somerset, on Friday evening. He has been bailed after giving DNA samples, and police are now awaiting the results.
The man, who has not been named, was noticed by a member of the public who thought he resembled a photofit picture of a suspect prepared by French police.
Caroline was 13 when she was killed in July 1996 while on holiday with a party from Launceston Community College, Cornwall. She was raped and smothered in a shared hostel dormitory in Brittany.
The Somerset arrest is part of a renewed drive to find the killer by police in France, who have been criticised over their handling of the case.Reuse content