Updated 11.40am with report of second incident

Four men were injured, two of them grievously, following an argument at a Sliema residence and another in St Julian's on Friday night. 

In the first incident, three Swedish nationals, all 32 years old, were allegedly attacked by a 36-year-old Libyan national, the police said. Five men in total were involved in the argument, which was reported around 8.30pm.

The aggressor was arrested by the police's Rapid Intervention Unit and is being held for further investigations. 

The three men were taken to hospital in an ambulance. One of the victim sustained grievous injuries with the other two walking away with slight injuries. 

It happened hours before another 35-year-old man was grievously injured following a fight in St Julian's early on Saturday morning. 

The victim, a Libyan national who resides in Pieta, was involved in an argument with another unidentified individual in Triq il-Knisja around 2.55am.

Passers-by provided the first assistance until an ambulance was called to the scene. The aggressor fled the scene and a search is ongoing. 

Police are investigating both cases.