The Metropolitan Police has declared a reported explosion at Parsons Green Underground Station as a terrorist incident.
Early photos from the scene show a bag on fire , after emergency services were called to the west London station during the Friday (September 15) morning rushhour.
Police were called around 8.20am following reports of a fire on the train.
For live updates on this incident, head to our live blog.
Deputy assistant commissioner Neil Basu, the senior national coordinator for counter terrorism policing, has declared it a terrorist incident.
Officers from the Metropolitan Police Service and British Transport Police attended the scene, along with colleagues from the London Fire Brigade and London Ambulance Service.
A Met Police spokesman said the force is aware of a number of people who have suffered injuries.
The spokesman said: "It is too early to confirm the cause of the fire, which will be subject to the investigation that is now underway by the Met's Counter Terrorism Command.
"The station remains cordoned off and we are advising people to avoid the area."
The force also urged the public to remain calm but alert and to contact police if they see or hear anything suspicious.
The full statement from the police said: "Officers from the Met's Counter Terrorism Command are investigating after an incident on a London tube train this morning.
"Police were called at approximately 08:20hrs on Friday, 15 September to Parsons Green Underground Station following reports of a fire on the train.
"Deputy Assistant Commissioner Neil Basu, the senior national coordinator for CT policing, has declared it a terrorist incident.
"Officers from the Metropolitan Police Service and British Transport Police attended the scene, along with colleagues from the London Fire Brigade and London Ambulance Service.
"At present we are aware of a number of people who have suffered injuries."
The statement goes on to say: "It is too early to confirm the cause of the fire, which will be subject to the investigation that is now underway by the Met's Counter Terrorism Command."
The statement went on to say: "The station remains cordoned off and we are advising people to avoid the area.
"Anyone who has information that would assist detectives is urged to contact the hotline 0800 789 321; if it's an emergency always call 999.
"Anyone with images from the scene is asked to upload them to www.ukpoliceimageappeal.co.uk.
"We urge the public to remain calm but alert and if you have any concerns, see or hear anything suspicious then contact police."
We are bringing you the latest developments as we get them on our live blog .
Keep up to date with the latest news in west London via the free getwestlondon app.
You can set up your app to see all the latest news and events from your area, plus receive push notifications for breaking news.
Available to download from the App Store or Google Play for Android .
