Massive Police Presence At Arizona Home in Connection to Nancy Guthrie Abduction

A massive police presence lit up the quiet town of Rio Rico, Arizona late Tuesday night and it's all tied to the disappearance of Savannah Guthrie's mom, Nancy.

Videos online show a swarm of law enforcement vehicles descending on a neighborhood less than 15 miles from the Port of Nogales, a major U.S.-Mexico border crossing.

The person detained for questioning's mother-in-law told reporters outside the house her son-in-law was the person detained, but insisted he has nothing to do with Nancy's disappearance.

The Pima County Sheriff's Department confirmed they're conducting a court authorized search at the location as part of the ongoing investigation into Nancy's disappearance.

We broke the story ... law enforcement sources told us the person of interest that was detained by sheriff's deputies for questioning earlier on Tuesday is NOT a member of the Guthrie family.

According to the Pima County Sheriff's Office, the person was stopped during a traffic stop south of Tucson.

As we first reported, Guthrie’s disappearance has sparked growing concern and a multi-agency effort to track down answers. Now, with federal agents on the ground and a search underway near the border, the case appears to be intensifying.

As we told you, the abductor was promising to return Nancy to Tucson within 12 hours of receiving the $6 million ransom ... which means they're currently somewhere within a roughly 700-mile radius of Tucson.

There were 2 ransom deadlines, both of which have passed ... even though Savannah tried reaching out to the kidnapper and even offered to pay up.

Tuesday afternoon we noticed activity for the first time in the Bitcoin account listed in the first ransom note that was sent.

This morning, the FBI released the first images of Nancy's apparent kidnapper ... and the feds blasted the footage out to the public on the same day they received the info.