A hero police dog was stabbed five times in the head while subduing a knifeman who broke an officer’s wrist.
Brave Kaiser is “lucky to be alive” after the horror attack in south London on Sunday night, the Met said.
He and handler PC Mark Woolcott were on patrol when they were called to an intruder alert in Orpington at around 11pm.
They responded along with other officers before finding a man down a track behind the house, the force said.
Kaiser then attempted to subdue the man, who stabbed him up to five times on top of his head and once below the eye.
But he held on despite the attack – long enough for officers to take hold of the offender.
A statement added: “[Kaiser] was rushed to the vets where thankfully the blows to the top of his head were found to have struck bone, narrowly avoiding lasting injury, or worse.
“He required stitches and was kept in overnight for observation but is expected to make a full recovery.
“In the struggle that followed the attack on Kaiser, another officer sustained a broken wrist and is expected to be off work for up to a month.”
Scotland Yard said the man responsible for the attack had left his house in Biggin Hill earlier the same evening armed with a large kitchen knife.
He is also believed to have used a golf club to smash the window of a car before disappearing into fields nearby.
The statement continued: “He is 43 and suffers from severe mental health issues. His family had alerted police to his disappearance and a search had been carried out but he could not immediately be found.
“Following the attack on Kaiser, the man was detained under the Mental Health Act and is now receiving treatment at an appropriate facility.”
Superintendent Emma Richard said: “I want to pay tribute to Kaiser and PC Woolcott for the immense bravery they showed in tackling this armed man. Kaiser was stabbed multiple times in the head and is lucky to be alive.
“My thoughts are also with the officer who sustained a broken wrist. I wish him a speedy recovery and hope to see him back on duty as soon as he is able.
“We should recognise that the man responsible for this attack was suffering from a mental health crisis.
“He is getting the care he needs now and a decision will be taken in due course as to whether it would be appropriate for any criminal charges to follow.
“Incidents where mental health is a significant factor can be unpredictable and sometimes dangerous.
“They make up an increasing proportion of the calls our officers respond to and present a unique set of challenges.”