Human Interest Body of Missing Pa. Woman Found in Creek a Mile Away from Where Her Car Crashed Into Tree Cassandra "Casey" Johnston was last seen leaving a friend's house on July 10 By Gabrielle Chung Published on August 2, 2021 07:10 PM Share Tweet Pin Email Cassandra "Casey" Johnston. Photo: Lower Southampton Police Department The search for Cassandra "Casey" Johnston — a 26-year-old woman from Bucks County, Pennsylvania, who went missing in July — has come to a tragic end. Johnston's body was discovered in Byberry Creek off Townsend Road in Philadelphia on Sunday, three weeks after her disappearance, according to officials. The Philadelphia Medical Examiner's Officer determined on Monday that Johnston died of blunt impact trauma, with her manner of death being ruled as an accident, local news station WPVI reported. Johnston was reported missing after she didn't return home from a friend's house in Philadelphia on July 10. She was last seen driving a silver 2016 Ford Focus. On Saturday, Kevin Ryan, a private investigator hired by Johnston's family, spotted a part of the woman's car in a wooded area while doing an aerial search of her route home, Lower Southampton Township Police Chief Ted Krimmel said at a news conference. Remains Found on Ca. Freeway in 1981 Now Identified as Missing Dallas Woman: 'Kept Me Up at Night' Johnston's body was found about a mile away from her vehicle after a day of searching, he said. Upon preliminary investigation, investigators believe that Johnston had trouble maneuvering a curve and went airborne over a guardrail, crashing her car into a tree about 49 yards from the road. Krimmel said that Johnston was likely ejected from the sunroof of her car and landed in a culvert, which then carried her body downstream after recent flooding in the area. A tornado that ripped through the woods on Thursday also likely broke some tall trees that made it impossible for investigators to see Johnston's car during previous aerial searches of the area, Krimmel said. "I think it might have knocked some of the higher foliage loose and when Mr. Ryan's helicopter got there, he could see what he thought was a silver piece of metal that turned out to be the car," Krimmel told reporters. RELATED VIDEO: Bodies of Missing Mich. Parents and 8-Month Son Found in the Woods Near Stuck Car: 'Tragic' Johnston's parents, Carolann and Joseph Johnston, previously told Dateline that their daughter was out with friends in Philadelphia's Chinatown neighborhood when she lost her phone. Krimmel said at Sunday's news conference that police would have found Johnston "right away" if she had had her phone with her. A GoFundMe campaign in support of the Johnston family was set up in July following her disappearance. As of Monday, it has raised more than $11,100. "I think it was nice to see how the community was reaching out to the family, offering support," Krimmel said. "I was kind of glad to see that people at least wanted to do something."