Little Angels Nursery in Calne has been closed as police carry out an investigation.
Police are not saying what the investigation is about but have said that a 37-year-old woman was arrested yesterday.
A spokesman for Wiltshire Police said: “We can confirm that police are conducting an investigation into allegations relating to Little Angels Nursery in Calne.
"The nursery has been closed by Ofsted and staff from the nursery are in the process of informing all parents of the closure.
“We can confirm that one woman, aged 37, was arrested on Saturday, August 16, and was taken to Melksham Police Station. She has since been released on police bail. Enquires continue.
"We are in the early stages of an investigation and it would be inappropriate to comment further on this matter.
“We are working closely with the local authority and any parents who have concerns regarding this matter are advised to call either Social Services -Emergency Duty Service on 0845 6070888 or during Monday to Friday between 0845hours and 1720hours call the Multi-Agency Safeguarding Hub (MASH) on 0300 4560108
“If you want to report a crime or think that you have information that might assist police you can also call 101 or alternatively, if you wish to remain anonymous please call Crimestoppers on 0800 555 111."
The nursery, in Curzon Street, Calne, was inspected by Ofsted on May 27 this year and received a good rating.
At the time of the inspection the nursery had 78 children on its roll ranging in age from 0-8.
The Ofsted report said: “Children make good progress in the areas of learning and development. Staff have a strong knowledge and awareness of the provider’s policies and procedures for safeguarding which they implement effectively to protect children’s welfare.
“Staff are calm and friendly which has a positive effect on children’s behaviour. Staff establish good relationships with parents, which underpin an effective key-person system. They involve parents in their children’s learning, which aids progress.
“The manager drives improvement well through effective evaluation that identifies areas to improve and which encourages staff to aim for higher standards, so benefitting children.”
Little Angels is based in a cottage in the grounds of Springfields Academy and on its website it says it is currently full for September 2014 but is taking bookings for September 2015.
Little Angels Nursery is privately owned by Rachel Cartmell who is also the manager. The nursery has seven woman and one man as full-time members of staff, according to its website.
The Gazette left a message on her mobile number asking if she wanted to comment on the closure by Ofsted and the police investigation.
An Ofsted spokesman said today: "We have suspended this nursery's registration."