A teenager was due to be questioned yesterday by detectives investigating the rape of an 11-year-old girl who was attacked at a supermarket.
Warwickshire Police confirmed that the 15-year-old boy was arrested at an address in Leamington Spa on Wednesday night.
The victim was assaulted in a toilet on March 2 at the Sainsbury's store on Leamington's Shires Retail Park.
A police spokesman said the 15-year-old was in custody at a Warwickshire police station awaiting questioning.
Detectives announced two weeks ago that they had compiled a list of more than 40 possible suspects following appeals for public help.
Officers also drafted in a "behavioural investigative adviser" to help the inquiry, which has involved 35 detectives and police staff.
Sainsbury's offered a £5,000 reward for information leading to the conviction of the offender.
The victim, who is said to have been left trauma-tised by the assault, was assaulted after leaving her mother to go to the toilet in the store.