The explosion also left several passengers fleeing in panic, the Tribune reported.
The injured have suffered facial burns after the reported blast in a bucket towards the rear of the District Line train.
A Metropolitan Police spokesman said, "The police were called at approximately 08:20 hrs on Friday, September 15 to Parsons Green Underground Station following reports of an incident on a tube train."
"The officers from the Metropolitan Police Service and the British Transport Police are in attendance along with the London Fire Brigade and the London Ambulance Service. We would advise people to avoid the area," the spokesman added.
"We have sent multiple resources to the scene including single responders in cars, ambulance crews, incident response officers and our hazardous area response team, with the first of our medics arriving in under five minutes," Wills added.
Wills further said that their initial priority is to assess the level and nature of injuries.
A witness reportedly saw "a flash and a bang" in a bag holding the container, which is said to have had wires coming from it, on the packed rush-hour carriage. (ANI)