California authorities said they believe that the remains of Kiely Rodni, a missing 16-year-old early high school graduate, have been recovered from a reservoir near where she was last seen more than two weeks ago.

"We recovered the vehicle, we recovered the vehicle last night," Nevada County Sheriff Shannan Moon said in a news conference. "We have located a decedent inside the vehicle. We believe it is our missing person. We have not been able to positively identify, but it’s more than likely."

The investigation is still active, she added.

The sheriff's department announcement comes a day after a volunteer dive team said it found her missing 2013 Honda CRV in 14 feet of water with a body inside.

KIELY RODNI CASE: SHERIFF EXPECTED TO MAKE MAJOR ANNOUNCEMENT AFTER VOLUNTEER GROUP FINDS SUBMERGED SUV

Kiely Rodni in a black dress

Kiely Rodni went missing on Aug. 6 just after midnight, shortly after telling her parents she was coming home. (findkiely.com)

Adventures With Purpose (AWP), a group with a popular YouTube channel that assists in missing persons cases, announced Sunday on Facebook that they found Rodni’s vehicle upside down in 14 feet of water with a body inside. Law enforcement previously searched the area by plane, helicopter, boat and with divers.

The vehicle was found in the reservoir upside down, Capt. Troy Sander said at the briefing, in an area that had already been "extensively searched" and was very close to where Rodni had last been seen. He said that investigators would look into the initial miss during debriefing.

Police arrived at the reservoir later and pulled the light-colored SUV out of the water, but authorities held off on official confirmation throughout the evening. Images of the vehicle show it has front-end features that resemble those of Rodni’s missing Honda.

MISSING KIELY RODNI: A TIMELINE OF THE 16-YEAR-OLD'S DISAPPEARANCE FROM CAMPGROUND PARTY

Police pull an SUV out of water

Inset: The SUV pulled out of the water near the Prosser Family Campground on Sunday. Background: Kiely Rodni's 2013 Honda CRV. (KTXL, Placer County Sheriff)

She was last seen late on Aug. 5 or early Aug. 6 at the party — which involved between 200 and 300 juveniles and young adults, according to authorities. There were drugs and alcohol present.

Extensive searches of the surrounding area by land, air and boat turned up nothing until AWP arrived over the weekend to assist. Authorities said the reservoir’s water level dropped more than three feet since Aug. 6 when Rodni went missing.

Kiely Rodni in pigtails adjusts her ring

Kiely Rodni was last seen at a rural campground near the border of California and Nevada around 12:30 a.m. on Aug. 6, according to local authorities. (findkiely.com)

Rodni’s disappearance under suspicious circumstances had initially been regarded as a possible abduction. Police interviewed more than 100 partygoers, and none of them said they saw her leave.

Sami Smith, a friend who said she had been with Rodni for the entire evening until she left the party around 12:20 a.m., said they’d met several new people but no one who seemed suspicious. However, she noted that Rodni appeared too drunk to drive.

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Authorities last week said they had interviewed "most" of the out-of-town visitors who attended the party, which was a high school graduation sendoff for students from different high schools around the area north of Lake Tahoe. Some guests were visiting the vacation community from as far as the Bay Area.

An autopsy was scheduled for Tuesday, authorities said. Toxicology results could take four to six weeks to come back.