Brave police detained a knife-weilding man with a Taser after he boarded a train brandishing the weapon and sparked panic among passengers.
Officers were called to Peckham, London, on Tuesday afternoon (18/02) following reports of a topless armed man suffering a mental health crisis.
By the time officers arrived at his reported location the man had made his way onto a train while still carrying the blade.
Pursuing officers eventually caught up and detained the topless man - believed to be in his mid-50s - using a Taser.
Footage from the scene shows cops in both plain-clothes and uniform marching the suspect along a train station platform following the arrest.
An officer following behind can be seen carrying a large knife on the video, which was shot by a person sat on a stationary train.
Some passengers posted on social media both during and after the incident describing their fears.
One said: "The driver of my @SouthernRailUK train to London bridge this afternoon handled the situation of a trespasser with a knife boarding the train so well!
"I applaud his calmness & making sure everyone was okay.
He allowed a few of us to hide in his carriage as it did escalate." A spokesperson for the Metropolitan Police said: "Officers were called at 12:20hrs on Tuesday, 18 February to an address in Queens Road, SE15.
"A man was reported to be at the location armed with a knife and having a mental health crises.
"Officers attended, but the man had left in a car.
"After a search of the area officers located the car and a police pursuit was authorised.
"The driver decamped from the car in Queens Road, and ran along railway lines to Queens Road Peckham Railway Station.
"He then boarded a train - which was in service and contained passengers - still armed with a knife.
"The pursuing officers located the man on the train, and deployed a Taser to detain him.
"London Ambulance Service have attended the scene and the man, believed to be aged in his mid-50s, has been detained under the Mental Health Act.
"There are no reports of any injuries to members of the public or officers." Detective Superintendent Nicky Arrowsmith added: "This incident highlights the challenges that police officers confront on a daily basis.
"I am very proud of the courage and determination of all the officers involved, and pleased that their work helped ensure no member of the public suffered any harm."