Two men are in hospital after they were attacked by a group in West Sussex.
Police are investigating reports a gun was used in the attack which happened at about 13:30 BST in Moat Road, East Grinstead.
One of the victims sustained a serious head injury and was taken to hospital by air ambulance.
Sussex Police believes the assault involved a "small group", and officers are searching for suspects who fled the scene in a grey Fiat 500.
Police said the condition of the man who was airlifted to hospital was understood not to be life-threatening.
The other man, who had an injury to his mouth, was also taken to hospital.
Det Ch Insp Emma Vickers said: "We are aware that initial reports suggested that a gun may have been involved and we are awaiting further information about the nature of the injuries and witness statements to establish whether that was the case."
She said it was believed the incident "was confined to these six individuals".
Paul Farrar was driving his wife, who is a key worker, to work when he saw one of the victims on the pavement before police arrived.
"A poor chap was lying there, with about a half a dozen people stood around and two people looking like they were kneeling down next to him trying to help," he said.
Hannah Turk, 29, said armed police were guarding the cordon and she saw paramedics carrying a stretcher from the scene.
"It really shocked me in terms of it being so dramatic and in a situation of where we should all be inside," she said.