"A tragic and senseless act that happened earlier today in Hallie involving a Halmstad Girl Scout troop has us all asking Why?" the Nokomis Service Area Girl Scouts said in a Facebook post, on a page that had days earlier been used to inform families about how their daughters could earn outdoor merit badges or remind the troop about Camp Nawakwa Shirt.
"Today Nokomis suffered a tremendous loss. It is with profound sadness that we join together in mourning the tragic loss of our Girl Scout sisters."
"Our hearts are broken for the girls and families of the Girl Scouts of the Northwestern Great Lakes," Sylvia Acevedo, CEO of Girl Scouts of the USA, said.
It was the third tragedy in the greater community of Scouts in less than five months.
On September 30, Boy Scouts on Long Island were headed to a hike when the group was slammed into by a suspected drunk driver, according to New York ABC affiliate WABC. Killed in the crash was Andrew McMorris, 12, who had just started taking flying lessons and hoped to one day earn his Eagle Scout badge.
And in June, a 14-year-old Boy Scout taking shelter from winds at a jamboree in northern Georgia was crushed in his tent. Another Scout, just a few metres away, wasn't injured.
In Wisconsin, the school, the community of Scouts and most of Chippewa were preparing to attend a memorial at the primary school the three girls who were killed attended.
The next day, officials announced, grief counsellors will arrive.