Scotland Yard detectives are investigating whether the culprits behind a "vile" effigy mocking the Grenfell Tower tragedy can be prosecuted.
Footage has surfaced online which depicts a large flammable model marked "Grenfell Tower", complete with paper figures at the windows, being placed over a naked flame and catching alight.
A total of 72 people perished as a result of the blaze in the west London block on June 14 last year, prompting an inquiry into how and why the disaster happened.
Metropolitan Police Commander Stuart Cundy, who is leading the investigation into the Grenfell Tower tragedy, said he was "frankly appalled by the callous nature" of the video.
He added: "So many people lost so many loved ones, and many more have been deeply affected. To mock that disaster in such a crude way is vile.
"I can't imagine the distress this video will undoubtedly cause to bereaved families and survivors."
He said the Met's Grenfell Tower investigation team is "taking this matter very seriously" and that any offences committed "will be fully investigated".
A Scotland Yard spokesman said it was "too early" to state what type of offences could have been committed, nor could they say whether Met officers were working with police from another force.
Khadijah Mamudu, whose mother and younger brother escaped the fire, said she was stunned by the footage.
She said: "I really don't know what to say, for once I'm honestly lost for words.
"The community is stronger together and even this vile act by flag-waving, intellectually challenged, brainwashed sheep won't derail the fight for justice, nor will it knock us off our stride as we walk forward, in dignity, in unity, in solidarity."
London's most senior firefighter has joined victims and their families in condemning the "appalling and disturbing video".
London Fire Commissioner Dany Cotton, who told the inquiry she is receiving therapy after suffering significant memory gaps after being at the scene of the harrowing blaze, said: "This is an appalling and disturbing video.
"To intentionally use and mock the Grenfell Tower fire in this way will cause deep pain and offence to the bereaved, survivors, the local community and all of the emergency services who will never forget that night.
"It cannot be justified on any level."
— London Fire Brigade (@LondonFire) November 5, 2018
It is not known when or where the video was recorded, or by who. But raucous laughter can be heard off-camera, with several bystanders speaking with southern English accents.
One can be heard saying: "Didn't it start from the tenth floor, though?", while others mockingly add: "Help me! Help me!" and "Jump out the window!"
Another says: "Here we go," as the fire takes hold.
At the end of the clip, someone else can be heard saying: "That's what happens when they don't pay their rent."
One witness is heard to refer to the model as being in "really bad taste", something sarcastically agreed by another person off-camera, who appears to count seven others stood around watching.
The video ends as the model is completely consumed by the fire, with one bystander saying: "Perfect."
Campaigners described the video as a "sickening act of hate".
Natasha Elcock, from Grenfell United, said: "It's a disgusting video. We hope that the police are taking this seriously.
"Not only is it extremely upsetting to survivors and people who lost family, it's hateful and offensive to everyone that has been affected by the tragic events of that night.
"We try to keep our focus on the thousands of people across the country who supported us in the weeks after the fire, the hundreds that walk with us every month on the 14th and everyone who is backing our fight for justice and change."
J4G's statement on circulating video pic.twitter.com/NQ81PKQKbc
— Justice4Grenfell (@officialJ4G) November 5, 2018
Justice4Grenfell said the video "caused great alarm and distress", and called on police to investigate.
A spokesman added: "We are disgusted and shocked at the inhumanity and callousness of those involved in this video.
"This was an unnecessary sickening act of hate against those who, through no fault of their own, have experienced the worst since 14 June 2017.
"This is clearly a hate crime and as a society we should never tolerate these types of blatant acts of hatred."
London mayor Sadiq Khan said: "I utterly condemn this sickening video. The horrific Grenfell Tower fire was one of the most devastating tragedies our city has ever suffered – and I urge social media companies to do the right thing and remove this content immediately."