Dozens of firefighters battled a major blaze near Elephant and Castle railway station in south London on Monday.
Fire crews raced to the scene shortly after 2pm London time after an explosion in the railway arches underneath the track.
A video posted on Twitter showed a blast from a building near the track.
The explosion sent a plume of smoke above the station and near large tower blocks.
London Fire Brigade said the fire had been brought under control several hours after the call for help.
More than 70 firefighters responded to the blaze, which spread to three commercial units in the arches, six cars and a telephone box.
“Please avoid the area and close all doors and windows,” firefighters said on Twitter.
Network Rail said trains were not stopping at the station.
“Trains are currently stopped, unable to proceed in the Elephant and Castle area,” it said.
“Emergency services are on site and we await confirmation that the area is safe for the passage of trains.”
Mayor of London Sadiq Khan said: “My thoughts are with all those affected by the very serious fire in Elephant and Castle, which is now under control. I’m in close contact with the Fire Commissioner and want to thank our emergency services who acted quickly to ensure residents & passengers were safely evacuated.”