Five people were left with non-life-threatening injuries, according to Greece's state broadcaster ERT.
A fault with radio communications caused air traffic controllers to temporarily suspend arrivals and departures.
The fire service says the body of an elderly man was found inside his home in the Togani area, close to where the fire started.
There have been no reported injuries, as Greece's transport minister condemns the "criminal" attack.
Tens of thousands of people demand action as they gather to remember the victims of Greece's worst railway disaster.
The girls from Bournemouth School for Girls have been chosen to represent the UK in Athens.
Ibi Akhtar, from west London, is starting the fundraising challenge in Crete, where his friend died.
A firefighter says this week's mega-blaze which reached the outskirts of Athens was like a war.
