There has been a significant increase in the number of people showing signs of sickness having spent time at a Lake Minnetonka party hotspot over Fourth of July.
In the latest update, Hennepin County Public Health said that as of 10 a.m. Wednesday, it had returned 140 phone calls from people who reported being ill having been at the "Big Island" area of the lake.
Of those, 116 have met the "case definition" of the Big Island outbreak, namely that they were there over Fourth of July weekend and have since "exhibited symptoms of vomiting and/or multiple episodes of diarrhea."
The number marks a significant rise from Tuesday, when 30-plus cases had been confirmed.
Health officials continue to investigate the cause of the sickness, with lab test results taken from affected individuals expected soon.
Further tests are being conducted on water taken from the lake in the affected areas.
It comes amid wider concerns about unsafe water following the closure of several beaches in the Twin Cities metro area.
Two beaches on Bde Maka Ska and Lake Hiawatha Beach in Minneapolis were closed over Fourth of July weekend because of higher-than-safe e.Coli levels, while beaches in Chaska and Excelsior have since closed for the same reason.