An 11-year-old Girl Scout was killed when a tree fell in a "freak accident" at an Indiana campground on Monday, officials said.
A 10-year-old girl and two women were also injured in the incident.
The Perry County Sheriff's Office said it received a call at around 11:30 a.m. local time about a tree that had fallen on several campers and volunteers at Camp Koch, the Girl Scouts of Southwest Indiana's resident camp facility, nestled along the Ohio River near the small city of Cannelton.
They were there to have a good time.
The victims were out for a morning hike on a gravel road on a fairly steep incline when the tree fell in what Perry County Sheriff Alan Malone called "very bad timing."
The group was heading back down the incline toward the mess hall when they were struck and became trapped under the tree, Malone said.
The 11-year old, Isabelle Meyer, died after suffering head and abdominal injuries, Perry County EMS officials said at a news conference on Tuesday.
Her grandmother, Cindy Meyer, told ABC News Isabelle has two younger sisters and loved the Girl Scouts and nature.
(MORE: Mother, 10-year-old daughter killed when car plowed into Girl Scout troop 'needed to be together')The entire Girl Scout family mourns the loss of one of our girls.
A 10-year-old girl had a hand injury and has been treated and released, Malone said.
A 50-year-old woman suffered head, neck and chest injuries, while a 55-year-old woman had a pelvic injury. The two adults are believed to be in stable condition, the sheriff said.
The sheriff called it a "freak accident" and said there won't be a criminal investigation. Malone, overcome with emotion, said, "They were there to have a good time."
(MORE: Girl Scouts fight to install menstrual hygiene locker in their school bathrooms)Girl Scouts of Southwest Indiana confirmed the "tragic death" of one of its members attending camp and said it has closed Camp Koch while the incident is being investigated.
"There is nothing we take more seriously than the safety and well-being of our girls and volunteers," the youth organization said in a statement. "During this difficult time, the entire Girl Scout family mourns the loss of one of our girls, and we ask for privacy for the individuals and their families as they grieve and mourn this tragic loss."
The "Girl Scouts of Southwest Indiana were extremely helpful and also cooperated throughout this investigation," Malone said.
ABC News' Esther Castillejo and Will Gretsky contributed to this report.