A man who falsely claimed that he lived with a family in the Grenfell Tower claimed more than £100,000 in accommodation and financial benefits intended for victims of the fire.
Three men from Croydon have been arrested in connection with a video that showed an effigy of Grenfell Tower being burnt.
The chairman of the inquiry, Sir Martin Moore-Bick, opened Tuesday's session by calling the video "offensive" and adding that "it must be shocking and distressing to all those involved ... whatever form their involvement took, whether as bereaved, survivors or indeed members of the wider community".
The five men range in ages from 19 to 55.
In June 2017 a total of 72 people perished in the blaze that engulfed the West London tower block - hundreds had their lives utterly devastated with the youngest person to die because of the incident being a stillborn baby. "We're coming to get you!" yells another participant, referring to the promises of emergency workers who instructed residents to stay in place and wait for help - help that didn't reach them in time. But raucous laughter can be heard off-camera, with several bystanders speaking with southern English accents.
The disgusting video on Twitter sees a group of adults placing a cardboard mock-up of the tower over a flame and watching it burn. A person can be heard saying: "Didn't it start from the tenth floor, though?", while others add: "Help me!"
At the end of the clip, someone else can be heard saying: "That's what happens when they don't pay their rent".
One person shouts "jump out the window" while another offers the original fire brigade advice before the scale of the tragedy was understood, saying "stay in your flats".
British Prime Minister Theresa May has criticised the "utterly unacceptable" video.
Cmdr. Stuart Cundy, who is leading the Grenfell Tower investigation, said in the statement: "I am frankly appalled by the callous nature of the video posted online".
"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".
Natasha Elcock, from Grenfell United, said: "It's a disgusting video".