Three men and a woman were injured on Wednesday afternoon when their car was involved in a head-on crash with a pick-up truck on the Gharghur bypass.
The crash took place at 2.40pm and involved a VW Polo and a DAF pick-up truck.
The injured, believed to be Hungarian, were travelling in the Polo.
The police said two of the passengers - a 30-year-old man and a 21-year-old woman - were seriously injured, while the driver, 26 and another passenger, 31, were slightly injured.
The road was closed for some time pending investigations.
Photos Jonathan Borg.