Man Tasered Near Buckingham Palace, Officers at the scene suggested that Mr Rehman was known to them and was mentally ill. He had previously worked at the Maharaja Halal butcher a mile from his home address, it was reported.
A police cordon was thrown around the scene just 30 metres from the palace gates.
The two knives Mr Rehman had been carrying, an Afghan-style hat, a set of prayer beads and his high-top trainers remained within the cordon alongside Taser barb, the wire released as the electrical current is discharged from the gun.
The Band of the Grenadier Guards played on through the melee as baffled tourists watched the incident unfold shortly before 12pm.
Josh Greenberg, a sixth-form student at St Paul’s School in London, said: “I was walking past the palace, heard some commotion in the area next to the Victoria Memorial [and] looked to my right, the guy ran out into the middle of the square with a knife at his neck.
“Within a few seconds he was surrounded by police horses and officers on foot. Less than two minutes later a car came with officers with Tasers.
“One stood in front of him and the other went around from behind and discharged the Taser then the police got him on the floor, kicked the knives away and put him in the back of a van.
“He was shouting but it was quite unintelligible. Police were clearly telling him to drop the knife and instructing public to get back.”