DigitalVision/Thinkstock(LONDON) — London Metropolitan Police are investigating a terror incident after an explosion injured commuters during the height of rush hour inside the Parsons Green station at about 8:20 a.m. local time.

A British government official tells ABC News the incident is being treated as a terrorism event, but at this early stage appears to be an isolated incident. An eyewitness also tells ABC News there were multiple injuries, but no fatalities. The London Ambulance service said they transported 18 people to the hospital, but none of the injuries are serious or life-threatening.

Police say the device did not fully explode.

Martin Abams, an eyewitness who was on the train, told ABC News that there was a minor explosion, which caused predominantly minor facial and burn injuries. He said the train had just arrived at the station and the doors had just opened when the explosion happened.

 We’re aware of an incident at #ParsonsGreen station. Officers are at the scene. The station is closed. More information as we get it.

— BTP (@BTP) September 15, 2017

“The tube had just pulled into the station, and as the doors were opening there was a loud explosion and ball of flame which moved along the corridor of the train just where I was,” Abams told ABC News. “I looked back and saw a bit of confusion with people rushing to get off the train. I saw a blue bag, with some smoke, and flames, which appeared to be coming out of the bag. I got off the train onto the platform. There were a number of people with singed hair and what appeared to be facial burns. I then went back onto the carriage to see if there were any casualties, but there were no casualties at all on the train. Everybody appeared to get off. There was nobody laying on the platform floor. I assessed that there were no serious casualties at that time.

“There was just the heat, the fireball and the noise, but no concussion as such.”

British Prime Minister Theresa May plans to hold an emergency cabinet meeting at 1 p.m. local time.

Metropolitan Police said on Twitter the incident was being treated as a terrorist incident.

“The emergency services attended and at this stage we are treating the matter as a terrorist-related incident and the Metropolitan Police counter-terrorism command will take responsibility for that investigation,” Deputy Constable of British Transport Police Adrian Hanstock said. “At this stage it’s little early to draw any full conclusions as to what the circumstances and cause of that explosion are and we are investigating and exploring that at the moment. We will get further information throughout the day but for now we just remind people to remain alert and report anything suspicious to the emergency services.”

 The Met’s Counter Terrorism Command are investigating after the incident at #ParsonsGreen tube station is declared a terrorist incident

— Metropolitan Police (@metpoliceuk) September 15, 2017

London Mayor Sadiq Khan condemned those who would perpetrate such an incident in a statement.

“Our city utterly condemns the hideous individuals who attempt to use terror to harm us and destroy our way of life,” Khan said. “As London has proven again and again, we will never be intimidated or defeated by terrorism.”

New York City Police Commissioner James O’Neill said there were no known threats to the city’s subway system, but reminded passengers to remain vigilant and aware of their surroundings.

London Ambulance said they responded to the scene in West London with multiple resources, including ambulance crews, incident response officers and its hazardous response team.

An eyewitness told the BBC that the train was “packed,” and several people were apparently injured when they were trampled trying to get off the train.

“I saw crying women, there was lots of shouting and screaming, there was a bit of a crush on the stairs going down to the streets,” eyewitness Richard Aylmer-Hall told the BBC.

#parsonsgreen pic.twitter.com/0OUV819EtE

— Sylvain Pennec (@sylvainpennec) September 15, 2017

Abams said the situation was managed well by train operators and everyone remained relatively calm.

This is a breaking news story, please check back for updates.

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