Four people were treated by paramedics and part of the Potteries Shopping Centre in Hanley was evacuated after a mystery substance was discovered in the toilets.

Staffordshire Police cleared the top floor of the centre in Hanley after the unknown substance was found this afternoon.

Tonight, police confirmed it to be a type of detergent.

Two members of centre staff and two emergency service workers were treated at the scene for irritation to the eyes and throat.

Emergency services were called after the substance was discovered by a member of staff.

Superintendent Bernie O'Reilly, from Staffordshire Police's Stoke-on-Trent division, said tonight: "A report was received this afternoon, Wednesday 22 October, by a member of staff at the Potteries Shopping Centre in relation to a substance found in the toilets on the top floor.

"To ensure the safety of the public it was decided to evacuate the top floor.

"We are now working with the other emergency services, including specialist staff from Staffordshire Fire and Rescue Service, and West Midlands Ambulance Service, to identify the substance and deal with it appropriately."