Armed police swooped on the Home Office headquarters this afternoon after a man was stabbed in the face in a vicious attack outside.
Dramatic photographs showed the victim being led away from the building in Westminster covered in blood, after he staggered inside following the attack.
Scotland Yard said officers had arrested a man on suspicion of grievous bodily harm and took him to a police station following the shocking incident at about 1pm.
The Met has confirmed to MailOnline that it is not ruling out terror as a motive, after unconfirmed media reports that the victim was a member of staff targeted due to him wearing a Home Office pass.
It comes just days after Home Secretary Priti Patel, who has an office in the building, gave police increased powers for stop-and-search amid a knife crime epidemic.
An injured man is helped by a medic and police outside the Home Office in London today
Pictured: Belongings at the scene in Westminster as forensics analyse items left at the scene
Police said the injuries suffered by the man are ‘currently being treated as life threatening’
Scotland Yard said ‘enquiries are ongoing into the exact circumstances of the incident’
An office worker opposite the building described seeing a man – thought to be the perpetrator – walk calmly down the road after the incident.
She said: ‘He was standing over there outside the Home Office and then he was putting something away in his bag, but I didn’t see a knife or anything.
‘He was putting something away and then he just calmly just walked off down the road as if nothing had happened.
‘Then people were being asked to go into the Home Office, they were being ushered in.’
Police officers were seen arriving on motorcycles and cars at the scene on Marsham Street, with ambulances and paramedics also in attendance.
Witness Gareth Milner said he was eating his lunch on the wall outside the building when ‘a number of armed police officers arrived on scene and entered’.
The stabbing comes after the new Home Secretary Priti Patel (pictured during her first interview in the role) promised to tackle to scourge of knife crime on London’s streets
‘Some time later a gentleman with quite a bloodied face and with dressing pressed into his face was escorted out of the Home Office by paramedics,’ Mr Milner added. ‘He was quiet and walking on his own feet, not being physically supported.’
Shaun Malston, 43, a property manager at Garton Jones estate agents opposite the Home Office, described seeing people running into the building after the stabbing.
‘I suddenly heard a lot of noise and commotion – people shouting – and people running into the Home Office,’ he said.
‘I happened to notice a guy by the tree over there, just sitting to the right of it, and then turned around and was putting something into a backpack.
‘A lot of people sit out there during lunch but he was probably one of the few that was left there because everyone else was running away and scattering, and he just put stuff, whatever, into his backpack and put it back on and just walked down (the road).’
He said he saw the victim walking out of the Home Office ‘with his shirt off, but he had a jacket on and he had blood all down his chest and he had a patch over his eye’.
Police officers arrive outside the Government building on Marsham Street this afternoon
Blood is photographed on the pavement outside the Home Office building this afternoon
A police officer in the doorway of the Home Office building in Westminster this afternoon
A police cordon outside the Home Office in London after the stabbing incident this afternoon
Mr Milner, who works nearby for the Centre for Policy Studies think-tank, said a police officer told him someone had been stabbed, but gave no further details.
Earlier, Mr Milner tweeted: ‘Lots of armed police and a cordon going up outside the Home Office. Gentleman with a bloodied face has been led out by paramedics.’
A barista working opposite the Home Office said she saw a man ‘full of blood’ walking out of the Government building.
The eyewitness said the victim was a man who appeared to be in his 50s and was not wearing a shirt as he walked out of the Home Office with police.
Police officers outside the Government building on Marsham Street in Westminster today
Police officers walk in and out of the Government building in Westminster this afternoon
Police officers arrived on motorcycles and cars at the scene on Marsham Street in Westminster
‘He had just trousers, nothing on top… He was full of blood. He was escorted by police and paramedics…
‘I saw just the police when the police came. He was coming out from the building – the officers come in and take him out.’
Ms Patel tweeted today: ‘All my thoughts are with the victim and their family following horrific unprovoked knife attack on Marsham Street.’
A Metropolitan Police spokesman said: ‘Police were called at 1.06pm on Thursday to Marsham Street, SW1 following a report of a man with a knife at the location.
London Ambulance Service attended the road where they helped the injured person
Ambulances and paramedics were seen outside the building in London after 1pm today
‘Officers attended to find one man with knife injuries. London Ambulance Service attended the address where they are with the injured party.
‘The injuries are not life threatening. One man (no further details) has been arrested on suspicion of grievous bodily harm and taken to a police station.
‘Enquiries are ongoing into the exact circumstances of the incident.’
A London Ambulance Service spokesman said: ‘We were called at 1:11pm today to Great Peter Street, SW1, to reports of an incident.
Police were called to the building following a report of a man with a knife at the location
A general view of the Home Office after the area was cordoned off by police this afternoon
‘We dispatched an incident response officer, a medic in a response car, a motorcycle paramedic and an ambulance crew. We treated a man at the scene and took him to a major trauma centre.’
A Home Office spokesman said: ‘The Metropolitan Police is investigating a knife attack which took place outside the Home Office this afternoon. The victim is receiving medical care.
‘This is a deeply concerning incident and our thoughts are with him and his family. As this is an ongoing investigation it would be inappropriate to comment further.’
The Home Office headquarters are located a short walk away from landmarks including Westminster Abbey and the Houses of Parliament.
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