Witness Amy Coop tweeted that she was with the man at Fishmongers Hall when attack occurred shortly before 2 p.m.

“A guy who was with us at Fishmongers Hall took a 5’ narwhal tusk from the wall and went out to confront the attacker,” she wrote. “You can see him standing over the man (with what looks like a white pole) in the video.”

She hailed the man for his bravery saying, “We were trying to help victims inside but that man’s a hero”.