A five-month-old baby was seriously injured in a two-car collision on the Tal-Barrani Road on Saturday evening.
The accident took place in the limits of Tarxien at 10pm.
The police said it involved a Renault Captur driven by a 58-year-old man of Swieqi and a Honda Fit driven by a 32-year-old man of Iklin.
A woman aged 31 and the 5-month-old boy were in the Honda.
Civil Protection Department officers were on site to assist the injured together with a medical team.
The four were taken to hospital for treatment, with the boy certified to have suffered serious injuries.
The 58-year-old man suffered slight injuries while the man and woman in the Honda were grievously hurt.
Magistrate Noel Bartolo is leading an inquiry.