Police are appealing for witnesses to an assault in Crawley.
The assault happened on Friday (September 15) in Goffs Park.
A Sussex Police spokesman said: “A 41-year-old man near the miniature railway in Goffs Park when he was approached by a man and woman.
“After a brief conversation the victim was hit once before the pair ran off in the direction of the level crossing on Horsham Road leaving the man with a serious facial injury requiring hospital treatment.
“The pair are white and aged between 18 to 20. The man is described as being skinny with light brown hair and the woman is described as having shoulder length dark brown hair.”
Detective Constable Kirstie Neal added: “We are appealing to anyone who was in Goffs Park at lunchtime on Friday who might have seen what happened. We are particularly interested in speaking to a dog walker who is believed to have been in the area at the time of the incident.
“The man is being supported and assisting police at this time. Patrols in the area have been increased and we ask that people remain vigilant and report anyone acting suspiciously.”
Anyone who saw what happened or has any information is asked to contact police online or on 101 quoting 625 of 15/09.