Police are hoping train passengers can help them catch a hooded attacker.
A 29-year-old woman was approached from behind and thrown to the ground.
The attack happened in Wormald Street, Dewsbury, near the town’s railway station, at about 5.40pm on Saturday.
The woman, who has not been named, suffered minor injuries.
The attacker ran off towards the Eightlands Road station entrance and police believe passengers may have seen him.
The 5.36pm Manchester Airport to Middlesbrough express had just pulled into the station.
The man is described as Asian, around 5ft 6in tall and dressed all in black. He had his hood up.
Anyone with information should contact Dewsbury and Mirfield Neighbourhood Policing Team on 101.
