A police helicopter was used this afternoon to try and trace a missing woman in Bushey because of concerns for her welfare.
The 21-year-old has been described by police as being 5 ft 5 inches, with dark brown shoulder-length straight hair.
She is wearing a grey tracksuit and black trainers with bright yellow stitching and carrying a pink handbag.
The police helicopter was originally being used to trace three men who ran from police in Oxhey Avenue. Foot patrols are now being used to search for the missing woman.
Anyone with information is asked to contact police via the non-emergency number 101.