Two men were attacked and knocked unconscious on their way to a Worthing pub.
They were kicked and punched by two men at Teville Gate, near Worthing railway station.
Their assailants, both in their early 20s, fled when two women screamed at them to stop.
The victims, aged 42 and 35 and both from Lancing, were taken to Worthing Hospital and treated for concussion, cuts and bruises.
Detective Constable Kim Clinch said: "It was a short-lived but nevertheless very frightening incident.
"Both are feeling extremely groggy and will probably remain in hospital for a number of days.
"At this stage we have managed to trace the two women who intervened and a man."
Anyone with information about the attack at 11.30pm on Friday should call Det Con Clinch on 0845 6070999.
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