Two weeks after the suspicious disappearance and possible abduction of California 16-year-old Kiely Rodni, the investigation led to the arrest of a local sex offender on unrelated charges, police say.

"The operation, which occurred on Thursday, Aug. 18, resulted in several sex registrants being found in violation of their terms, with one arrest being made and criminal charges to be filed on another," the Placer County Sheriff’s Office announced Friday morning. "The Truckee Police Department routinely conducts similar sweeps and is committed to aggressively pursuing prosecution of those offenders found to be out of compliance with any probation or parole terms."

Rodni’s unsolved disappearance prompted the compliance checks, but the arrests were not directly related to her case, according to investigators. Truckee police did not immediately respond to a request for more information about the arrested suspect.

Across state lines in nearby Incline, Nevada, deputies performed a similar check on a sex offender Wednesday but said it had no connection to Rodni’s disappearance. Back in California, a multi-agency task force investigating the girl's case is also asking additional witnesses to come forward. 

KIELY RODNI: CALIFORNIA POLICE ‘MODIFYING’ SEARCH EFFORT NEXT WEEK AS FEW SIGNS OF MISSING TEEN EMERGE

Missing Kiely Rodni flyer near campground

A missing person flyer for Kiely Rodni is shown at the Tahoe National Forest, where she was last seen at a party on Aug. 6. (Michael Ruiz/Fox News Digital)

Rodni was last seen at an outdoor party within the Tahoe National Forest that stretched from the evening of Aug. 5 into Aug. 6. 

The 16-year-old early high school graduate was drinking and "partying" with friends and was likely too inebriated to drive, one partygoer, 18-year-old Sami Smith, told Fox News Digital.

MISSING KIELY RODNI: MASSIVE SEARCH AS FRIENDS REVEAL TEEN'S LAST KNOWN FOOTSTEPS IN POSSIBLE ABDUCTION CASE

There were about 200 to 300 people in attendance, mostly juveniles and young adults, according to the Place County Sheriff’s Office.

Of those, detectives have interviewed between a third and half of them, according to Angela Musallam, the sheriff’s public information officer.

Kiely Rodni dress and on surveillance split

On Tuesday, the sheriff's office shared a surveillance image that showed Rodni's outfit on the night she went missing. (Findkiely.com, Placer County Sheriff)

"Although our detectives have interviewed over 100 partygoers, they would still like some more cooperation," she told Fox News Digital on Friday.

Investigators have still not been able to speak with anyone who actually saw Rodni leaving, and the sheriff’s office is asking for anyone who has not yet spoken with detectives to do so. Authorities are also asking for people to continue submitting tips, including videos and photos taken at the party. 

Rodni texted her mother around midnight saying she was headed home. At 12:33 a.m. on Aug. 6, her phone last pinged near the site of the party, a clearing in the woods between the Prosser Family Campground and Prosser Creek Reservoir outside Truckee.

MISSING KIELY RODNI: INVESTIGATORS FIND NEW VIDEO OF VANISHED TEEN ON NIGHT OF PARTY; REWARD INCREASES TO $75K

Kiely Rodni Honda CRV and sticker

Kiely Rodni's SUV is also missing — a silver 2013 Honda CRV with California license plate 8YUR127. It has a small ram-head sticker on the back window, under the rear wiper blade. (Findkiely.com)

More than a week of searches focused on the immediate and surrounding areas turned up no signs of Rodni. Her vehicle, a silver 2013 Honda CRV with a ram head sticker under the rear windshield wiper, is also unaccounted for, police say.

MISSING KIELY RODNI'S MOTHER SAYS AMBER ALERT ‘SHOULD HAVE BEEN ISSUED IMMEDIATELY,’ WANTS TO STAY ‘POSITIVE’

Kiely Rodni was seen wearing a pink and white 'Odd Future' hoodie

The Placer County Sheriff's Office says Rodni appeared on video earlier in the night she went missing wearing a pink and white "Odd Future" hoodie. (Placer County Sheriff's Office, FindKiely.com)

The party also included visitors from out of town, and Musallam said that "the majority of them" have been identified.

Investigators said Monday they were scaling down the massive search effort, which involved days of aerial surveillance and dive teams, to a task force-based investigation.

"We are still looking for any clues, videos, tips, any information to help us to put pieces together and help us to direct where we're going and how we're going to continue to do a search," Capt. Sam Brown of the Nevada County Sheriff's Office said during a news briefing.

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

Kiely Rodni poses near palm trees

Rodni was last seen on Aug. 6 at the Prosser Family Campground in Truckee, California. (findkiely.com)

Rodni is described as 5 feet, 7 inches tall and about 118 pounds. She has blonde hair and hazel eyes. She has a tattoo on her ribs of the number "17." She has a nose ring and several other piercings and was wearing three gold necklaces the night she went missing, according to her friends.

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Rodni was wearing green Dickies pants, a black studded belt and a black spaghetti-strap bodysuit, according to authorities. She also was seen on video in a pink and white hoodie reading "ODD FUTURE" earlier on Aug. 5. She may have also been in possession of a dark gray hoodie with Lana Del Rey lyrics.

Anyone with information is asked to call the Placer County Sheriff’s Office’s dedicated tip line at 530-581-6320. Callers can remain anonymous.

There is a $75,000 reward for information leading to her whereabouts.