An argument broke out between a group of people in a Birkirkara establishment on Sunday at 5.15pm, the police said.
The establishment is located on Triq is-Santwarju.
The police went on site and preliminary investigations revealed that a group of people started an argument and attacked a 38-year-old man from Mosta and a 48-year-old woman from Siggiewi. The aggressors fled the scene before the police arrives.
The man and woman were taken to Mater Dei Hospital for care and were certified as having suffered grievous injuries.
Police investigations are ongoing and three men are being held to assist in the investigation.