Police seeking whereabouts of Robert Kevin McCullough who escaped custody on Friday

A police manhunt is underway for a 39-year-old man who escaped custody in Perth on Friday.

Police are urgently seeking the whereabouts of Robert Kevin McCullough who escaped from custody about 4.45pm on Friday in the Perth CBD.

He is described as 175cm tall, of medium build, with blue eyes, brown hair and a fair complexion.

Members of the public should not approach McCullough if sighted and should call police immediately on 131 444.

Anyone with information relating to his whereabouts or his recent movements should contact Crime Stoppers on 1800 333 000 or via www.crimestopperswa.com.au.