The Nottingham Inquiry has heard how Valdo Calocane headbutted and punched a police officer 2 years before the fatal attacks
The former student killed Barnaby Webber, Grace O'Malley-Kumar and Ian Coates in 2023.
Valdo Calocane headbutted, punched and swung handcuffs at a police officer who was helping doctors to detain him two years before he fatally stabbed three people, the public inquiry into the Nottingham attacks has heard.
Calocane, who was diagnosed with paranoid schizophrenia, had been refusing to take his medication when he launched an attack on Police Constable Barnaby Pritchard, of Nottinghamshire Police, on September 3 2021, causing swelling to his face.
The former student killed University of Nottingham undergraduates Barnaby Webber and Grace O'Malley-Kumar, both 19, and grandfather Ian Coates, 65, and attempted to kill three more people in the early hours of June 13 2023.
On Wednesday, Pc Pritchard told the inquiry, which is being held in London, that he received a call to attend Calocane's address in Nottingham where he was refusing to be be detained by doctors under mental health laws.
Calocane was "very calm" when they arrived at his address and "was very unemotional with any response", Pc Pritchard said.
The officer added: "At the time, he wasn't demonstrating any warning signs that he could begin assaulting me.
"As soon as I stepped in the room, he began just swinging completely out of the blue.
"He began punching me repeatedly.
"As a collective, we managed to restrain him against an item of furniture inside the room.
"He tried headbutting me, and did headbutt me, while I was trying to restrain him."
The inquiry heard that Calocane swung handcuffs at Pc Pritchard "as a weapon", but the officer believes he missed.
The officer was left with swelling on his forehead and bruising on his left cheek, with the witness adding: "I had pain and discomfort, they were quite sore."
A Taser was deployed twice and Pava spray, an irritant spray, was used to restrain Calocane, the inquiry heard.
In body-worn camera footage played to the inquiry, Calocane can be heard saying when Pc Pritchard and three female officers arrived: "I don't have a history of mistreating women", before saying: "Gentlemen, if you want to take me out, I prefer you do it."
After his attack on Pc Pritchard, Calocane said: "You didn't go down", the inquiry heard.
Asked by counsel to the inquiry Rachel Langdale KC what his interpretation of this comment was, Pc Pritchard said: "It was possibly some male bravado - he expected the force of his blows to put me to the floor."
In the footage, Calocane can be heard grunting after being tasered and saying: "No more of that."
Calocane was taken in a marked police van to hospital because he had been tasered, the inquiry heard, before he was taken to Highbury Hospital, a mental health facility.
The inquiry was previously told that two months before this incident, Calocane pushed his flatmate against the wall, tried to get into his locked bedroom during the night, and then stalked him by following him home on two occasions.
These incidents were reported to the police but no further action was taken against Calocane, the inquiry heard.
The inquiry continues.