A man with an extensive criminal history is on the run after escaping custody at the Perth Central Law Courts.

Police have warned Robert Kevin McCullough should not be approached and instead authorities should be contacted immediately.

The 39-year-old has been evading authorities since appearing before a magistrate on Friday for accusations of serious sexual crimes.

CCTV of him fleeing through the Perth CBD about 4.45pm on Friday has been released.

He was last seen at the Stirling Gardens area and at Elizabeth Quay.

Police said he was known to frequent the Perth metropolitan area and officers have been in contact with McCullough’s known associates.

“We’re still exploring the circumstances of how Mr McCullough left the Perth Central Law Courts,” Detective Superintendent Kellie Taylor said.

“It’s not believed that any level of violence was used in his escape and has more to do, we believe, with deceit and trickery.”

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

Anyone who sees him is warned to keep away and contact police immediately.