A spokesperson for the family of missing California 16-year-old Kiely Rodni urged patience Monday morning hours before authorities are expected to make a major announcement in the case and after a volunteer group claimed to have found her remains underwater near where she was last seen.

Investigators are expected to hold a news briefing at 11 a.m. PT regarding the SUV and body discovered underwater near the Prosser Family Campground Sunday, more than two weeks after Rodni and her silver 2013 Honda CRV both vanished from a party in the area.

"At this time, I have no word from Kiely’s family as to the validity of yesterday’s social media posts indicating that Kiely and her car have been found," said Linda Luchetti, a retired Salt Lake City communications professional who volunteered last week to act as the family’s media coordinator. "This has not been confirmed to me by the family or by the Placer County Sheriff’s Office."

Adventures with Purpose, a group with a popular YouTube channel that assists in missing persons cases, announced Sunday on Facebook that members found Rodni’s vehicle upside down in 14 feet of water with a body inside. AWP said it was holding its own separate news briefing at noon PT.

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

Police pull an SUV out of water, with an image of Kiely Rodni's 2003 Honda CRV

Inset: The SUV pulled out of the water near the Prosser Family Campground Sunday. Background: The Placer County Sheriff's Office released this image of a silver Honda CRV. (KTXL, Placer County Sheriff)

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.

The area, near the border of California and Nevada, had previously been searched by dive teams, boats and from the air.

Her vehicle also had a distinctive ram head sticker on the rear windshield, under the wiper, police have said. The missing girl had several tattoos and piercings.

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)

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She was last seen late on Aug. 5 or early Aug. 6 at the party – but despite dozens of interviews, deputies said they found no one who saw her leave the area.

Kiely Rodni closeup with earring and nose ring

Search efforts for Kiely Rodni are ramping up in Truckee, California. (findkiely.com)

The party consisted of between 200 and 300 juveniles and young adults, according to authorities, and drugs and alcohol were consumed.

Extensive searches of the surrounding area by land, air and boat turned up nothing until AWP arrived over the weekend to assist.