According, to police, at 03:40 on Sunday an ambulance picked up a man alive, who had a stabbing wound in the neck, and took him to the Red Cross hospital, where he died a short time later.
Another man aged 23, was transferred and is being treated at the same hospital with a gunshot to the abdomen.
The police officers that rushed to the scene found a weapon inside a flower pot as well as a shell casing.
According to eye-witness reports, two groups of at least ten persons in their early twenties came into conflict over petty reasons. One group called n associated who pulled a gun that misfired. He was then stabbed in the neck by one the opposing group.
The Attica Security Directorate has launched a preliminary investigation.