By Mark Savage BBC music reporter

A charity concert featuring The Chainsmokers is being investigated after footage appeared to show fans ignoring social distancing regulations.

The concert, called Safe & Sound, took place on Saturday night in the Hamptons and was billed as a "drive-in music experience".

But video taken from the stage showed crowds of people outside their cars, standing in close proximity.

New York governor Andrew Cuomo said he was "appalled" by the footage.

Announcing an investigation into the concert, Cuomo wrote: "We have no tolerance for the illegal and reckless endangerment of public health".

Skip Twitter post by @NYGovCuomo

Videos from a concert held in Southampton on Saturday show egregious social distancing violations. I am appalled.

The Department of Health will conduct an investigation.

We have no tolerance for the illegal & reckless endangerment of public health.pic.twitter.com/gf9kggdo8w

— Andrew Cuomo (@NYGovCuomo) July 28, 2020

End of Twitter post by @NYGovCuomo

The state's health commissioner, Dr Howard A. Zucker, said he was "greatly disturbed" by reports that the concert "involved thousands of people in close proximity, out of their vehicles, [in] a VIP area where there was no pretence of a vehicle, and generally not adhering to social distancing guidance".

'Rampant violations'

In a letter addressed to the supervisor of the town of Southampton, where the concert was held, Dr Zucker demanded a report into the event, with a 24-hour deadline.

"I am at a loss as to how the Town of Southampton could have issued a permit for such an event, how they believed it was legal and not an obvious public health threat," Dr Zucker wrote in the letter.

He also asked: "Why was it allowed to continue when it became clear violations were rampant?"

The town supervisor, Jay Schneiderman, who was also listed as a performer at the concert, acknowledged that "aspects of the event violated the permit".

"They opened up a VIP area that was not part of the concert" approved by the town, he told the local newspaper Newsday. "We would never have approved a gathering area."

The event's organisers, In The Know Experiences and Invisible Noise, said in a statement that they had followed "all proper and current protocols," with attendees assigned to designated areas, spaced two metres apart.

Guests' temperatures were checked and "security guards regularly patrolled the area to encourage mask wearing and promote social-distancing guidelines," they added.

Speaking to Buzzfeed news, the organisers added that dividers separated parties in the contested VIP area, and that "guests were also instructed that they would not be allowed to leave their designed spots for any reason other than to use the restroom".

Concert-goers who spoke to Buzzfeed also said they "felt very safe" and that fellow fans were "being responsible" during the show.

An estimated 2,000 people attended the gig, with ticket prices ranging from $850 (£661) to $25,000 (£19,450). Proceeds went to charity, according to the event's website.

Other performers at the event included the chief executive of Goldman Sachs, David M. Solomon, under his stage name DJ D-Sol.

The investigation into the Safe & Sound concert comes as the UK government holds "pilot shows" to test how live music could resume after the Covid-19 lockdown.

Last week, Beverley Knight played to a reduced-capacity audience at London's Palladium theatre; while indie musician Frank Turner will play a similar show at the Clapham Grand on Tuesday.

However, plans for a major tour of drive-in gigs, featuring acts like The Streets, Kaiser Chiefs, Dizzee Rascal and Sigala were recently called off, with organisers saying the "latest developments over local lockdowns" meant they couldn't proceed "with any confidence".

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