A 9-year-old girl died at Oregon beach after a sand hole she was digging collapsed on her.

Isabel Grace Franks was vacationing at the beach in Lincoln City, nearly 80 miles southwest of Portland. While playing in the sand  Friday evening she dug a pit that was about three to five feet deep and sat in it. The sand hole then collapsed and suffocated her. People tried pulling her out but to no avail.

According to Lincoln City police Sgt. Brian Eskridge, after the girl and her siblings dug the large hole, she sat inside to find out how deep it was. "She was sitting inside, and the hole collapsed. We believe she was under the sand around five minutes," said Sgt. Eskridge.

According to the Associated Press, firefighters and law enforcement officials arrived at the scene just after 5 p.m. Officers removed the unconscious girl from the pit and began CPR on her. She had been in the dugout for around seven minutes; she was rushed to the hospital where she was declared dead.

Tracey Dudley, who witnessed the incident, said she initially thought it was just kids playing. But she called 911 when she realized that people were desperately trying to dig the girl out, reports CNN affiliate KATU.

Collapsing of a sand hole is a rare incident. According to a 2004 Mayo Clinic study, dry sand burial can totally surround and compress a person with no air pocket for breathing.

"Although accidental sand burial has its own set of clinical problems, clearing the airway is the main focus of treatment. Airway management at the scene of the incident may be crucial and lifesaving," the Mayo report states.