A woman and a man were grievously injured in a crash on Triq Valletta in Mosta late on Sunday.
The police said the traffic accident took place at around 9.20pm.
A 36-year-old man from Birkirkara was behind the wheel of a Peugeot 308, while a 32-year-old man, who was slightly injured in the crash, was driving a BMW 318.
A 30-year-old woman from Santa Venera who was riding in the BMW was later certified to be suffering grievous injuries.
A 33-year-old woman from Cospicua and an 11-year-old boy were in the Peugeot.
Investigations are ongoing.