The porter at Fishmongers' Hall who was attacked by a terrorist wielding a knife, grabbed a ceremonial pike from the wall and used it to try to stop the killer, the inquest has been told.
Lukasz Koczocik was injured during this attack as Usman Khan grabbed the pike and stabbed the porter in his arm and hand, resulting in Koczocik dropping the weapon.
Khan stabbed graduates Saskia Jones, 23 and Jack Meritt, 25, at a Cambridge University prison education conference, on November 29 2019.
He then made his way onto London Bridge, where he told his pursuers to "call the police" before being shot dead, the inquest has heard.
Mr Koczocik explained how he had been on the lower ground floor of Fishmongers' Hall, putting up Christmas decorations in the staff canteen when the housekeeper ran downstairs screaming "someone's got stabbed".
"I ran upstairs, literally ran upstairs, to check what had happened because I thought it was just an accident that had happened.
"I see three men throwing and holding different objects like a chair, signs saying 'Mind the steps', trying to defend themselves.
"It looks like a brawl to me, it wasn't that serious. I went through the first doors into the lobby, the reception area.
"At first I noticed the trestle tables were in disarray, one had been flipped over, and then I noticed who they were fighting with, the man with two knives.
"He had a thick jacket, he had a black beard, that's all I could notice," He said.
Khan was shielding himself from objects that were being thrown at him, such as a chair that was smashed over his head.
"I must admit I was surprised, shocked and probably I froze for a few seconds and then some of the pursuers began to back off," Mr Koczocik recalled..
"For some reason I decided to grab this boarding pike that was attached to the wall. I went through the doors and grabbed the pike," he added.
The boarding pike was described as being a long wooden spear with a metal end.
"I realised what he was trying to do, so I tried to stab him," Mr Koczocik added.
"A couple of times I tried to hit him, stab him in the face, but he got me off very easily. Then I got him in the stomach but it didn't do any damage - I heard a metallic clink and I thought he had some armour under his jacket."
Khan was concealing a fake suicide belt underneath his grey puffa jacket.
"I managed to land a strike on his belly, he grabbed the pike with one hand still holding the knives and I couldn't shake him off.
"While I was holding it, he cut me on the hand and cut me on the shoulder and then it becomes quite blurry
"I dropped the pike, he cut the tendons in my hand so I couldn't grip it. I moved back.
"This bit is quite blurry. He was coming towards me, at that same moment I noticed people were with their weapons, a Narwhal tusk and fire extinguisher and they were coming to help me."
The tusk had also been grabbed from the walls of the building.
"They crowded him so he started moving back. I remember he was shouting, 'get the police'.
"He was trying to open the doors himself and get out onto the streets. Honestly, I don't remember how the doors were opened. He ran out straight onto the street."
Mr Koczocik pursued Khan out onto the street along with three other men.
CCTV footage captured Khan being followed onto the streets at 2.01pm, just five minutes after he had stabbed Jack Merritt in the toilets.
"I was just following him, not much further than two or three metres behind him. He was running towards the London Bridge and all I could do was shout at them, 'He's got a knife' so that they moved away from him."
Mr Koczocik followed him as far as some anti-vehicle bollards, and told the inquest: "He was becoming crowded again, I saw the policemen came with a taser.
"At this point I realised there was no more danger and I tried to walk back to the Fishmerman's Hall."
At this point was when he heard gunshots as Khan was shot.
Khan held a knife to a maintenance workers throat, as he tried to make his way out onto the street, the inquest was told.
Andrew Ransom was involved with setting up for the fifth anniversary event for the Learning together project that morning.
Just before 2pm, he heard the fire alarm and came down the corridor past the ladies bathroom.
"There was a big trail of blood from my right, past the sofa, going towards the reception security office.
"I walked in slightly and then looked down, looked up and I see a man there coming towards me with a knife and put a knife on my chest.
"He was slightly taller than me he had a big jacket on, looked quite stocky and I think a baseball cap, and a dark beard.
"He put a knife on my chest I realised what it was. The knife touched my actual shirt. He said 'open the door'.
"I told him I didn't have a key or fob to that. He said it again, 'just open the f**king door'."
Mr Ransom told the inquest that he began moving slowly towards the security office door as he heard shouting start come from the doors to the rest of the building on his right.
"If I got towards the security office it would be a safer place to be, I edged towards that. He had the knife on my chest saying, open the door.
"There was a lot of shouting coming from my right through the glass doors. I heard somebody say get the police.
"He was looking more towards the doors but following me and then the doors opened and people came rushing in.
"It took his attention away from me a little bit so I managed to move a bit along the wall," he said.
"One or two had the Narwhal tusks from the display in the vestibule. Someone, I'm not sure who, they brought a chair down on his head which broke open but didn't make much difference."
"He seemed to go down a bit but didn't go to the floor," Mr Ransom added.
Khan's attention was then directed toward the other group as he made a "stabbing motion towards them" and "seemed at one point to be getting the upper hand".
Mr Ransom then realised that one of his colleagues, Gareth Watkins, was inside the security office, attempting to keep the door shut with his shoulder, protecting another member of staff as well as Jack Merritt who had staggered inside.
"The attacker said to me open the door, again. Gareth Watkins, he told me to open the door. There was an injured man in reception and he needed medical help urgently," Ransom said.
"I paused because I did actually think if I opened the door and it gave him access to London Bridge and the people outside, I had no idea what was going on.
"He could run into any amount of people and I did not know what was going to happen next."
But at that point his colleague said: "You've got to open the door he's in very bad need of help"
"So I opened the door and let him out," Mr Ransom said. "I turned to him and said we've opened the door. He turned around opened the door and went outside."
Khan then retreated down the stone steps and onto the street, before he changed his mind and came back up, banging on the glass of the doors, however Mr Ransom and his colleague were holding them tightly shut.
As Khan "walked normally" onto London Bridge, they opened them once again.
"We were shouting to people, he had a knife and to stay away," Mr Ransom said.
Khan was followed by others in the hall as Mr Ransom headed back inside, rushing to the aid of Jack Merritt, who was being assisted by Simon Larmour, one of Merritt's colleagues.
"I went in there and asked him what was wrong and he said a stab wound to his chest. I asked him his name he said his name was Jack.
"I asked Jack if he could hear me and I got no reaction from him at all. There was a lot of blood, it looked like more than one wound."
Ransom retrieved a first aid kit, took Merritt's shirt off and bandaged his arm, searching for any other wounds as police arrived on the scene.
However, Merritt went into cardiac arrest and was declared dead after being carried down the street to waiting HEMS emergency doctors.