It was among the worst fires in modern British history: The blaze that gutted Grenfell Tower in London last year killed more than 70 people, displaced hundreds more and marred the lives of the mostly low- and middle-income residents who lived there.

But to a group celebrating Britain’s annual Bonfire Night, it was a joke.

In a widely shared video that circulated on Monday, a group of people laughed as they burned an effigy of Grenfell Tower, which included paper cutouts of residents in the windows. “Help me! Help me!” one person mocked as flames overtook the model tower. “Jump out the window!” another shouted.

Brown paper was used to represent at least some of the residents trapped inside the tower, which in real life was home to ethnically diverse families and many Muslims.

Politicians quickly condemned the video, and the police said they were investigating whether any crime had been committed. Justice4Grenfell, a community group working for justice for the residents of Grenfell Tower, called the act a hate crime.