This is the dramatic moment armed police swoop in on an 'acid attacker' who seized a London bus and threatened the driver and passengers with a corrosive substance.
Footage shows armed police surrounding a 109 bus and asking members of the public to move away and stand back.
More than five police cars with their sirens on gather around the vehicle as police begin to set up a cordon.
Officers in blue chemical suits approach the bus before an officer shouts over a megaphone for the man to 'stand up and make your way off the bus now.'
Two officers stand at the middle door of the bus, waiting for the man to come down before they storm the bus, stunning him with a taser and wrestling him into the seat with police shields as they remove the potentially corrosive substance from him.
Footage shows police storming a double-decker to arrest a man who threatened a bus driver and passengers with what was believed to be a corrosive substance
The man could be seen being dressed in an orange jumpsuit, before being strapped to a gurney and taken to hospital for medical evaluations
Emergency services, including officers in specialised blue chemical suits (pictured), were called to the scene in Croydon
Following the arrest, chemical experts were called to the scene to assess the substance and it was later found to not be harmful
Officers then storm the bus to arrest the attacker.
The attacker was snared by police after they stormed the double-decker bus and he was stripped in the street.
Emergency services, including Metropolitan Police's Territorial Support Group, clad in blue chemical suits, were called to the scene in Croydon at 8.30pm on yesterday.
The incident began when a 44-year-old man boarded a 109 bus in Brixton and subsequently started smoking.
The man was confronted by passengers and the situation escalated quickly when the man took out a bottle of what was believed to be a corrosive substance.
A three-hour stand-off took place between police and the 'acid-armed man'. It is understood passengers left the bus and the substance had not been thrown at anyone and nobody had been reported injured.
Police detained the subject who could be seen being dressed in an orange jumpsuit, before being strapped to a gurney and taken to hospital for medical evaluations.
It is believed the man had taken drugs and police said his condition is not believed to be life-threatening.
Emergency services (pictured) assessed the man who was taken to hospital for medical evaluations as police believe he had taken drugs. His condition is not believed to be life-threatening
A police cordon was put in place as negotiations between emergency services and the man continue
The Metropolitan Police issued a statement urging people to avoid the area and asked pedestrians and drivers to seek alternative routes
Following the arrest, chemical experts were called to the scene to assess the substance.
The Metropolitan Police confirmed that the substance was 'not found to be harmful'.
The area from Brigstock Road down to Thornton Heath Garage was cordoned off and a safety perimeter was put in place to contain the situation and prevent any harm to the public.
The Metropolitan Police issued a statement urging people to avoid the area and asked pedestrians and drivers to seek alternative routes.
The motivations behind the man's actions are unclear.
In a statement, Croydon police said: 'Police responded to calls on London Road, Thornton Heath shortly after 8.30pm last night. A man had threatened bus passengers with an unknown substance.
Nobody was held hostage. The man made threats and everyone else on the bus immediately got off. The substance was not thrown.
Shortly before midnight, the 44-year-old man was arrested for affray. The substance was found not be harmful.
Taser was discharged prior to his arrest and officers believe the man had taken drugs. As a precaution, he was taken to hospital. His condition is not believed to be life-threatening.
All cordons have now been lifted.
There is currently a police presence in London Road, Thornton Heath.
'We were called to the location shortly after 8.30pm to reports of a man threatening bus passengers with an unknown substance. The substance has not been thrown at anyone and nobody is injured.
'All passengers and the driver have left the bus. '