A 22-year-old man fell from a height of one storey in the early hours of Monday morning.
In a statement, the police said the young man, from the Czech Republic, suffered serious injuries after he fell from one wall, landing on another, on Triq Mikiel Anton Vassalli, in Msida, just before 3am.
Police sources said they were investigating whether the young man, who was accompanied by friends at the time of the incident, was under the influence of alcohol.
The Civil Protection Department and an ambulance were called onto the scene to assist the young man who was taken to Mater Dei Hospital for treatment.