One person was injured and several buildings were extensively damaged by an explosion in central Athens that led to a fire early, officials and witnesses said.
One person who suffered burns was taken to hospital, Giorgos Mathiopoulos, the head of workers at the National Centre for Emergency Care, told Skai TV on Wednesday.
The pre-dawn blast occurred 200 metres from the ancient Temple of Olympian Zeus on the busy Syngrou Avenue.
Debris littered the street a day after a severe snowstorm swept the capital disrupting traffic and stranding thousands of people.
At least 18 firefighters used seven engines to battle a blaze at one buildings and have nearly brought it under control, the fire brigade said.
As dawn broke, they forced their way into damaged stores to free several people trapped inside.
It was not immediately clear what triggered the blast or the fire, officials said.
"We have a fire, there was a blast before that," said a fire brigade commander at the scene
Traffic was halted in the area.