Updated 2.50pm
The Regional Road, southbound, was closed to traffic on Thursday morning after a car overturned following a traffic accident off Swieqi.
The police said the accident happened at about 7.45am at the junction to Paceville, near the traffic lights in Triq Mikiel Anton Vassalli, St Julian's.
A 57-year-old woman who lives in St Paul's Bay was grievously injured in the accident while a 48-year-old woman who lives in Birżebbuġa and a 12-year-old girl suffered slight injuries.
The police said the older woman was driving a Toyota Yarris, the younger one a Toyota Vitz.
The 12-year-old was a passenger in the Vitz.
Civil Protection personnel assisted all three on site and they were then taken to Mater Dei Hospital by ambulances.
The police are investigating.