A man looks at his phone while passing a sign for curbside takeout in Portland's Monument Square.

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The same day a group of southern Maine business owners sued Gov. Janet Mills to lift the 14-day self-quarantine mandate for out-of-state travelers, another wrote to Mills urging her to keep it in place.

Saying that it was too soon to relax the required self-quarantine for visitors upon arriving in Maine, a group of 80 businesses sent a letter to Mills saying that they didn’t want to see more Mainers infected and hurt progress already made against the virus.

“Portland is irrefutably the most at-risk destination in Maine,” according to the letter, which was mailed to Mills and her administrators on Monday. “Many of us aren’t sure we want to reopen when we’re permitted, let alone how to do so.”

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“The travel quarantine is one of the only protections that we feel allows us a fighting chance to maintain our low case numbers and to protect our workers and ourselves,” the letter continued. “Lifting the quarantine and inviting in out-of-state tourists would create an entirely new strain on an already precarious system that we are just learning to navigate.”

The letter follows a lawsuit filed by owners of campgrounds and restaurants in southern Maine seeking an injunction to lift the 14-day requirement. Mills on Monday also announced a significant broadening of coronavirus testing in Maine.

The lawsuit further alleges that Mills’ plan to allow restaurants and other businesses in 12 rural counties to reopen this month while keeping non-essential business shuttered in Androscoggin, Cumberland, Penobscot and York counties is unlawful discrimination based on where they’re located.

The letter, meanwhile, says that reopening too soon and creating more viral spread would “undermine local consumer confidence” about being in public if tourists flooded local streets and businesses. The 80 co-signers said that an earlier appeal by the tourism industry violates common sense and that Mills should maintain the quarantine until enough immediate testing is available for out-of-staters.

“The worst-case scenario would be to start over and have everything to this point be for naught,” the letter states.