Two tourists were injured in a knife attack near the Acropolis, Greece's most visited tourist site, on Tuesday morning, police said.
The attacker stabbed a Greek American man and woman near the entrance to the Acropolis Museum at the foot of the historic Acropolis hill.
According to police, the woman suffered minor injuries to her leg, while the man was more seriously injured after being stabbed in the arm.
Authorities quickly detained the suspect, and both victims were taken to hospital by ambulance for treatment.
Police have not yet identified the attacker but said he appeared to be experiencing psychological problems. The motive for the attack is still under investigation.
Violent attacks of this nature are uncommon in Greece. In April, an 89-year-old man was arrested after allegedly opening fire with a shotgun at a social security office and a courthouse in central Athens, injuring at least four people in an incident reportedly linked to grievances over social security.
The Acropolis, home to the nearly 2,500-year-old Parthenon and several other ancient monuments, is one of Greece's most famous landmarks. Around 4.6 million people visited the site last year.