Two bystanders are being hailed as heroes after helping British police subdue convicted terrorist Usman Khan after he killed two people on the London Bridge.

One bystander, a chef named Lukasz, was armed with a narwhal tusk while the other wielded a fire extinguisher. Cell phone video taken during the Friday attack shows both men confronting Khan.

A third man, a British transport police officer in plain clothes, grabbed Khan and threw him to the ground while taking the attacker’s knife.

Queen Elizabeth II hailed the bystanders’ and officers’ bravery in a statement released Saturday.

“I express my enduring thanks to the police and emergency services, as well as the brave individuals who put their own lives at risk to selflessly help and protect others,” she said.

Lukasz is from Poland and works as a chef in Fishmongers Hall, where Khan’s attack began before spilling onto the London Bridge. After the commotion started, Lukasz grabbed a five-foot ornamental narwhal tusk off the wall of the historic hall and rushed outside to confront the attacker.

Lukasz and the other men were some of the first to stop Khan’s attack in which he killed two people and injured several others. Lukasz was also injured, suffering a cut on his hand from the knife-wielding attacker.

British police arrived soon after and shot and killed Khan, who was wearing a fake explosive vest.

British authorities had released Khan from jail on license, or with conditions such as a curfew after he was convicted of “terror offenses.” Prime Minister Boris Johnson said in a statement that Khan should never have been allowed to walk free.