A wild beach party where hundreds of people flouted social distancing measures has become the source of a new coronavirus outbreak.
Multiple revellers at a Fourth of July party in Michigan have tested positive for the virus, prompting health officials to warn other partygoers to get tested too.
A video taken at Diamond Lake caught thousands of American partygoers dancing with no regard for social distancing measures.
The clip shows people packed shoulder to shoulder on the beach and in the water at an event to mark the country's national Independence Day public holiday.
Now a week on from the packed party, the state's health department have confirmed an outbreak and urged anyone who attended the event to get tested and self-isolate.
"Several individuals tested positive for COVID-19 this week after attending the festivities at the Torch Lake sandbar over the Fourth of July holiday," a post on the local health authority website reads.
It goes on to state that those who tested positive were not able to identify everyone they had come into contact with, meaning "numerous individuals may have been exposed to COVID-19" as a result.
Hundreds of people could be affected by the outbreak but final figures are not yet known.
The party drew widespread criticism online and caused one expert to declare the US was in "free fall" with its virus situation.
Social media users branded attendees "idiots" adding the footage was "embarrassing".
"When I saw the diamond lake party video I was so embarrassed and disappointed in what I was seeing. Please stay home and stay safe," one wrote on Twitter.
"Unbelievable! This is disgraceful," another wrote.
"How many times do these idiots have to see this happen in order for them to stop doing it. They are sick from mere stupidity, thinking they are invincible & somehow smarter than expert medical professionals," someone else said.
Across the country, clubs, pubs, bars, dance halls, beaches and gyms have been reopening. And coastal states – such as Florida – has seen people flock to beaches to celebrate summer break.
The Fourth of July weekend was described as the "perfect storm" by Boston Medical Centre infectious disease expert Dr Joshua Barocas.
"The combination of travel, the combination of reopening – perhaps in some cases, too early – and the combination of people not necessarily following some of these preventive guidelines," he said.
Gatherings and parties in the US have become the worrying centre of many virus spikes.
Last week a 17-year-old girl died after attending a party at her church with more than 100 kids who were not social distancing.
Carsyn Leigh Davis, 17, attended the social gathering on June 10 but less than two weeks later, she died on June 23 while on life support.
While a family in Texas ended up with 18 members infected from a surprise 30th party, with a man in his 80s currently remaining on life support where he's been since June 17.
A pub was also the centre of a mass infection incident when a woman revealed she and 15 of her friends contracted the virus after meeting for a drink. Seven of the pub's employees were also diagnosed with COVID-19.