A knifeman chased and threatened terrified bystanders after stabbing a passenger on a train, witnesses said.
Police swarmed on Forest Hill station after the "horrific" attack at about lunchtime.
Passengers fled the station screaming with terror after the armed man reportedly shouted threats at people on the scene in south London.
Witnesses said there was a huge presence of emergency services at the station as they warned people to avoid the area as the attacker was "ranting on the streets".
Forest Hill station stabbing: Knifeman shouted 'I want to kill a Muslim'
Sky News
December 12, 2016, 3:34 pm
A knifeman who reportedly stabbed a rail passenger at a train station in southeast London shouted, "I want to kill a Muslim", according to a witness.
One man was injured in the attack at Forest Hill station at around lunchtime on Monday.
Eyewitnesses described the "horrific" attack and its aftermath on Twitter.
One person wrote: "The perpetrator is currently ranting on the streets. Beware."
Another tweeted: "#foresthill The attacker shouted " Who is Muslim, I want to kill a Muslim approached the guy sitting with his wife on the 1st carriage."
Shellby Curry, 24, was with her one-year old child when she saw a man "waving what looked to be a knife in his hand" near the station and screaming words like "Muslims f****** hate them, kill them all".
"I was walking along and someone stopped and said 'be careful, he's got a knife'.
"As I looked around there he was. I just grabbed my baby and ran across the road. Looking back (I saw) him marching up and down waving his arm about."
Miguel Oliveira, 36, said he came "face-to-face" with the attacker, who he described as "shouting uncontrollably".
"He was walking towards me and he was shouting stuff like 'Death to Muslims' and 'Go back to Syria'," he said.
British Transport Police said the incident was not being treated as "terrorism-related".
A spokeswoman said officers were sent to the station after reports of a serious assault at 1.18pm.
"One person has been arrested following the incident and is currently in police custody," she said.
"One man was treated by ambulance staff at the scene and is currently en route to hospital."
The pigs (police) refuses to call it terrorism. This is were i think muslim scholars and leaders need to come out. It should be left to activist from cage or mpacuk to do this. Scholars are out in a flash to condemn muslim doin attacks.
This cannot be undone and I am sure it will be greatly appreciated.
We apologise but you have been denied access to report posts in this thread. This could be due to excessively reporting posts and not understanding our forum rules. For assistance or information, please use the forum help thread to request more information. Jazakallah