The Staten Island Chamber of Commerce has sent out a letter warning businesses to consider closing their doors on Saturday ahead of a planned protest march against police brutality.

In a letter with the heading "security alert," the Chamber of Commerce explains that while march organizer Al Sharpton has pledged that the march will be non-violent, “there is no guarantee that everyone in attendance will act sensibly."

The march, which is being planned by Sharpton's National Action Network, will no longer cross the Verrazano Bridge as originally envisioned, and stick exclusively to Staten Island, leading the Chamber of Commerce to fear for the march getting out of hand. Dubbed "We Will Not Go Back," the march will start at 11 a.m. and conclude at 1 p.m., the organizers have said. Afterwards a rally will last until 3 p.m., after which buses will return protestors to points in Brooklyn and New Jersey.

Some store owners are already anticipating trouble. A local bagel store owner told WCBS that he had canceled the morning shift at his store. “There is only going to be two people, which is me and one of my cooks. To me, I don’t want to risk it just in case it does turn out to be big.” Because there's nothing merchants fear more than a ton of foot traffic.

The march, which is also being sponsored by the SEIU, The UFT, and the NAACP, will feature the family of Eric Garner, the Staten Island man killed by a police chokehold last month, as well as the family of Michael Brown, the unarmed teenager who was killed by police in Ferguson, Missouri this month.

"I'm going to try to close by rally time," a store owner told the Staten Island Advance. "I'm not worried about the regulars acting badly, it's the people from the other boroughs who I'm worried about." Not that he has anything against people from other boroughs, mind you—we're sure some his best friends are from the other boroughs!