A crazed Romanian repeatedly stabbed a policewoman in the face with a pen while loitering in a back garden.
Adrian Popa, 40, was tasered, but continued attacking the officer last summer in the rear of a property in Manor Park Crescent, Edgware.
At the Old Bailey he received three years and ten months imprisonment after pleading guilty to inflicting actual bodily harm and making threats to kill.
The court heard police were called by a resident at around 10.25am on Sunday, August 16, last year after Popa was spotted in the garden of an address.
He was subject to bail conditions that prohibited him from being in the area.
Officers attended and Popa began jumping fences in a bid to evade police.
He was pursued and apprehended by an officer.
A police taser was deployed and discharged, but was unsuccessful.
Popa launched a ferocious attack on the officer, stabbing her in the face multiple times with a pen and threatening to kill her.
Colleagues arrived and a police taser was again deployed and discharged.
He was eventually arrested and taken to hospital as a precaution prior to going into police custody.
The officer was treated at the scene by paramedics from the London Ambulance Service before being taken to hospital.
Following a period of recuperation the officer has since returned to work.
Detective Constable Huss Ahmed said: "The officer in this incident is incredibly lucky, but for sheer fortune her injuries may well have been life-changing or worse, and we could have been looking at a very different investigation.
"I am glad Popa has admitted his guilt, and will now serve a custodial sentence.
“This serves a reminder that we will pursue anyone who attacks our colleagues, and will work to put them before the courts to face justice."
Chief Inspector James Noble, of the North West Command Unit, said: "This example highlights the risk that police officers face when they go to work.
“No officer should expect to be attacked in this way.
“Popa is a violent man who will now face the consequences of his abhorrent actions that day.
“We have and will always work to pursue charges against those who assault emergency workers."