(CNN) — The body found inside a submerged car in Northern California on Sunday belongs to teenager Kiely Rodni, who disappeared from a camping area about three weeks ago, police confirmed.

Hundreds of officers and volunteers have been searching for the 16-year-old since she was last seen at the Prosser Family Campground around 12:30 p.m. on August 6. Authorities initially treated her disappearance as a kidnapping, in part because they were unable to locate her vehicle, the Placer County Sheriff’s Office said.

After search teams found a body inside a car that was submerged in Prosser Lake, authorities said it was “more than likely” it was Kiely. An autopsy found that to be true. according to a statement posted on Facebook by the sheriff’s office.

Kiely’s cause and manner of death were not released, and the investigation into her death is ongoing, according to the statement.

“The Placer County Sheriff’s Office and the Nevada County Sheriff’s Office are in communication with Kiely’s family and offer our deepest condolences during this extremely difficult time,” the post read.

Nevada County Sheriff Shannan Moon previously said the vehicle was “located within a search zone where we have been searching since the beginning of our operation.”

The volunteer diving group Adventures with Purpose, which often participates in underwater searches, located the vehicle, Moon said. He was found face down about 14 feet below the surface of the lake, which has dropped nearly three feet since the teen was reported missing, Nevada County Sheriff’s Capt. Sam Brown said.

Kiely’s family said in a statement Monday that they are “forever grateful” for the support they have received during the search.

“We have weathered a storm of unfathomable strength, and it is purely thanks to the army of warriors, matriarchs, healers, and helpers who sustain us that we are still standing today,” the statement said. “As we accept this sadness under the shadow of death, the rising sun shines down on us, reminding us not to mourn our loss, but to celebrate Kiely’s spirit and the gift we all receive in meeting her. Kiely will be with us even if we don’t get her back.” “.

Between 200 and 300 young people attended the party at the camping site where Kiely was last seen, according to authorities.

The land is about 17 miles north of Lake Tahoe and about 37 miles from Reno, Nevada.