A man was stabbed in the chest in an altercation between two groups in Reading.
The stabbed man, who is in his 20s, and a 19-year-old man who was hit with a bottle and has head injuries, are in hospital.
The incident happened in Strathy Close between 21:30 BST on Sunday and midnight on Monday following a party.
Det Insp Richard Jarvis said a thorough investigation is being carried out to establish what happened.
He said he wants people who left the scene in a white car shortly before police attended to come forward.