One man is in a critical condition in hospital after he was stabbed when he intervened in a fight in Dublin's Temple Bar.
The 33-year-old is being treated at St James' Hospital following the incident on Saturday evening.
A second man - a 24-year-old - was also stabbed on the same evening. His injuries are not believed to be life-threatening.
Gardaí in Pearse street are appealing for witnesses to both incidents.
Reporter with the Herald Robin Schiller said the man who was seriously injured was attempting to break up a fight.
"This man was trying to stop a fight from happening, and unfortunately suffered very serious injuries in doing so," he said.