A teenager helped save his younger sister from an alleged kidnapper by shooting the suspect with his slingshot, Michigan authorities said.

The 8-year-old girl was mushroom-hunting in her backyard in Alpena Township on Wednesday when "an unknown male appeared from the woods," the Michigan State Police said in a press release on Friday.

"The suspect had come through the woods onto the property and came from behind her, grabbed her like you'd see in the movies -- hand over the mouth, arm around the waist -- and was attempting to pull her into the woods," Lt. John Grimshaw with the Michigan State Police told ABC Traverse City affiliate WGTU .

The girl was able to break free, police said. Her 13-year-old brother also witnessed the attack and shot the assailant in the head and chest with his slingshot, police said.

Grimshaw called the teen's actions "extraordinary."

"He really is the one that ... I believe saved his sister's either life or from something seriously bad happening to her," Grimshaw told WGTU. "He should be commended for it."

The suspect fled the area but was located by state troopers hiding at a nearby gas station and was able to be identified in part due to injuries from the slingshot, police said.

"The suspect had obvious signs of injury sustained from the slingshot with wounds to his head and chest," police said.

The suspect -- identified as a 17-year-old from Alpena -- was taken into custody and allegedly confessed to detectives that he "planned on severely beating the victim," police said. He was lodged in the Alpena County Jail without incident, police said.

The suspect was arraigned on Thursday on one count of attempted kidnapping/child enticement, one count of attempted assault to do great bodily harm less than murder, and one count of assault and battery, according to police.

His bond was set at $150,000 and his next court appearance was scheduled for May 17, police said.

The suspect is being charged as an adult but his name has not been released by police.