Police are hunting a man who punched a young woman in the face in a “shocking and unprovoked” attack before stepping onto a train at Willesden Junction.

Officers have released CCTV images of a man they would like to speak to in connection with the assault, which happened at the north west London transport hub on Tuesday August 13.

Police Constable Roy Ward, said: “The victim, a 23-year-old woman from Brent was waiting at Willesden Junction station on platform five at around 1.45pm. As a man walked past the victim, he suddenly turned around and punched her in the head, causing the victim’s glasses to break.

“Luckily the victim was not left with any visible injuries, but this was a shocking and unprovoked assault.”

The apparently random attack echoes the case of Michael Ayoade, 34, who was jailed for four years in February for knocking a teenager unconscious and attacking university student in east London last year.

In November Ayoade, from Plaistow, was caught on CCTV jogging up behind a 16-year-old girl in Plaistow High Street before punching her in the head and leaving her lying unconscious on the ground. A week later he attacked student Daniella Montieth at Plaistow station.

On the August assault, PC Ward said: “We do not tolerate violence anywhere on the rail network and I’d urge anyone who recognises the man pictured, or who may have witnessed what took place, to come forward and assist officers in this investigation.”

Anyone with information is asked to contact British Transport Police on 0800 40 50 40 quoting background reference B5/LNA of 13/09/2013 or call Crimestoppers anonymously on 0800 555 111.