Commuters in London are facing severe disruptions this morning (Friday 4) after a major fire brought Tube trains to a halt.
The blaze began underneath railway arches in Roxeth Green Avenue in South Harrow around 1am.
London Fire Brigade (LFB) deployed 100 firefighters and 15 fire engines to contain the fire, which was under control by 4am.
There are no reports of injuries.
The fire at railway arches in South #Harrow is under control and there are no reports of injuries.
— London Fire Brigade (@LondonFire) July 4, 2025
We’re likely to remain on scene for several hours and severe disruption is expected on the Piccadilly Tube line as a result of this incident.https://t.co/3hFGlBo5h3 pic.twitter.com/tSii1Dx7DD
However, parts of the Piccadilly line between South Harrow and Uxbridge remain closed.
Transport for London (TfL) reports that there are also severe delays on the westbound line only between Acton Town and South Harrow.
London Underground tickets are being accepted on local bus services in the interim.
LFB received the first of around 40 calls about the fire at 1.18am and mobilised crews from Harrow, Wembley, Stanmore, Ruislip and surrounding fire stations to the scene.
Two 32-metre turntable ladders attended and were used as water towers to help extinguish the fire from above.
A drone was also deployed, providing the Incident Commander with a greater situational awareness of the incident.
Road closures are currently in place in Roxeth Green Avenue, near the junction of The Arches, and are expected to remain in place through the morning.
Roxeth Green Avenue connects the Northolt Park area in the southwest to the Roxeth area of Harrow in the north.
It runs underneath the Piccadilly Line near the junction with The Arches, an industrial road which takes traffic northeast towards Rayners Lane.
According to the LFB, an unknown number of gas cylinders at the site are believed to have exploded during the early stages of the incident.
Firefighters safely removed two further cylinders and cooled them to an ambient temperature, as gas cylinders can explode when exposed to heat.
Local residents were advised by authorities to keep their windows and doors closed because of the smoke.
The cause of the fire, which severely damaged vehicle workshops, businesses and other commercial properties, is under investigation.
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