The first coronavirus infections in California took place in a nail salon, according to the state's governor.
Governor Gavin Newsom revealed the source of the outbreak after being asked why beauty parlours will be among the last businesses allowed to re-open following lockdown restrictions.
He said the cases spread despite "higher levels of sanitation" usually found in salons, Los Angeles Times reports.
Speaking at his daily press briefing on Thursday, he said: "This whole thing started in the state of California, the first community spread, in a nail salon.
"I just want to remind everybody of that and that I’m very worried about that."
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He added this shows how easily the deadly bug can spread, given that salons often take hygiene precautions such as wearing gloves and face masks, even prior to the pandemic.
It is not known where in the state or at which salon the infections took place.
Despite his warning, customers were reportedly seen heading to a beauty parlour in Yuba City, north of California's capital Sacramento, for manicures and pedicures on Wednesday.
California has been one of the worst-hit US states during the coronavirus pandemic, suffering 2,611 deaths and recording 63,699 cases.
The US has now become the centre of the global health emergency, having recorded 1.3m confirmed cases - a third of the total across the world.
The country's first coronavirus deaths were recorded in California in early February, after the highly contagious bug began spreading from New York to other states before stay-at-home advice was issued.
However, as the country struggles to deal with a cratering economy, a number of states have begun easing lockdown restrictions despite the worsening pandemic.
As of today, California moved from Stage 1 to 2 of its gradual re-opening, under which non-essential manufacturing, retail businesses offering pick-up, schools and childcare facilities have resumed.
Offices have also been allowed to re-open with social distancing and hygiene precautions if working from home is not possible.
However nail and hair salons, gyms and cinemas, which are deemed to be more risky, will not be allowed to resume business until Stage 3.
Newsom has not yet specified a timeline for when the state will move to the next phase.
