Two robbers are on the run after a police officer was threatened with a machete during a smash and grab raid on a luxury jewellers in the City.
Police said one man was arrested in nearby Gravel Lane, and two others fled the scene.
A City of London Police spokesman said armed police were on the scene, adding: "An officer at the scene was threatened with a machete when he confronted the group. The machete has been recovered.
"There are no reports of any injuries at this time."
The men were still at large at 8pm this evening, a City of London Police spokeswoman said.
Grant Hook, 41, who was making his way to an eye test, said: " I was in a taxi coming down Bishopsgate, there was a big crowd standing outside where it happened.
"I saw a guy running with a crash helmet on with a machete in his hands. It was over in a flash.
"My taxi driver went ‘oh look he has got a machete’ and I thought ‘oh Jesus’. It was a little bit distressing."
Military researcher Jane Robinson, 39, who lives nearby said she saw the aftermath of the incident while working in Artizan Street Library.
She told the Standard: "Some overalls and some of the other things to do with the robbery were found near where I'm sitting.
"There's an underground car park underneath this building and the person went into the underground car park. The outside is still cordoned off, although he's been apprehended now."
A worker from an office nearby told the Standard: "They have cordoned off Gravel Lane and armed police are there. We've been told that the incident is still in progress".
A witness said police were gathered in Houndsditch, between Liverpool Street and Aldgate.
A corporate lawyer who works near the scene tweeted: "Some kind of machete attack outside the office!"
Another witness said on twitter: "Our building is on lock down - nobody allowed in or out atm".
Daniel Bunyan tweeted: "Apparently there's a nutter running around with a machete outside our office. Area is locked down."
And another worker posted: "Someone with a machete holding up a shop near our building. Scary times."
One person tweeted: "Kicking off in the city - armed robbery/ machete madness apparently."
Pictures showed the front of the high-end jewellery shop with the front door glass smashed and a sledgehammer lying on the ground nearby.
