An 18-year-old Italian man was hospitalised early on Thursday after falling off a wall into a pool deck in a San Ġwann apartment block.
The police said the incident happened in Birkirkara Road at about 5.45am. The wall was about one storey high.
The police are investigating what the young man was doing there, amid reports that the man may have been drunk and had tried to jump into the pool.
His medical condition was described as serious.