A man dragged a foreign student towards bushes in Portslade in the early hours of this morning (Sunday 13 May).
The 20-year-old managed to escape his clutches before phoning for help.
The attacker had tried to engage his victim in conversation on a night bus from Churchill Square in Brighton. But he was clutching a wine bottle and mumbling in what appeared to be a drunken manner.
She got off at the bus at Portslade Station at about 4.20am and walked up Carlton Terrace and turned into Old Shoreham Road where the man passed her.
Sussex Police said that as the woman turned into Foredown Drive, the man turned and ran towards her, grabbing hold of her and dragging her towards some bushes.
She told him to let her go and he did. She then ran off and phoned for help.
The man was described as black, about 30 years old, 6ft tall, slim, with short curly black hair and a moustache.
He was wearing a white T-shirt, trousers that were not jeans and tennis shoes.
Detective Inspector Mark Cullimore said: “This was very disturbing for this young visitor to the UK.
“Fortunately, she managed to escape her attacker, but it is very important that we find this man.”
He urged anyone who was in the area or on the bus or who saw the attack or someone matching the suspect’s description to call 101.