A masked intruder, a $6 million ransom and the abduction that has puzzled the world.

When US viewers of the Today Show tuned in to watch the morning broadcast on last Monday, they saw something unexpected. Co-host Savannah Guthrie hadn't shown up for work.

Moments later, her colleagues addressed the absence, revealing that Guthrie is living every family's worst nightmare.

Her mother, Nancy Guthrie, 84, is missing — and authorities allege she was taken from her home. Over a week later, she is still missing.

Her children are distraught, police have released footage of a possible suspect and the world is watching on — puzzled and disturbed.

"We do believe that Nancy was taken from her home against her will," Pima County Sheriff Chris Nanos confirmed in a press conference last Tuesday (Wednesday morning in Australia).

Nancy was last seen by loved ones just before 10pm on Saturday evening, police confirmed. When she failed to show up to church the next morning, her family went to Nancy's home. She was nowhere to be seen.

The family reported her missing at around 12pm on Sunday. The search is ongoing.

What is the update on the Nancy Guthrie investigation?

Savannah Guthrie and her mum Nancy. Image: Today Show

Ten days after Nancy Guthrie went missing, police are still investigating her disappearance and seeking information from the public, per CNN.

The FBI has today (Tuesday in the USA) released surveillance footage from outside Nancy's front door taken the night she disappeared.

"As of this morning, law enforcement has uncovered these previously inaccessible new images showing an armed individual appearing to have tampered with the camera at Nancy Guthrie's front door the morning of her disappearance," FBI Director Kash Patel said in a statement on X.

Four photos and two videos, published on the bureau's website, shows a masked and armed individual picking up what appears to be foliage from the front yard and covering the camera with it.

Despite the camera being disconnected just before 2am on the morning of her disappearance, the new footage was recovered from "residual data located in backend systems", FBI director Kash Patel said.

The Guthrie family were notified of the new footage by the FBI but, according to reports from the NBC, they do not recognise the person.

Hours later, police confirmed they had detained a subject during a traffic stop in Tuscon and were questioning them in relation to Nancy's disappearance.

Police have released new footage of a masked individual captured from Nancy Guthrie's front door. Image: FBI

After the FBI released the photos, Savannah Guthrie posted them to her personal Instagram account, pleading for anyone with information to come forward.

"We believe she is still alive. Bring her home," Savannah captioned the post.

"Someone out there recognises this person. We believe she is still out there. Bring her home," she wrote in a second post featuring the new video footage.

Since the photos and videos were released, officials have seen an increase in calls, CNN reports.

There have been reports of alleged ransom letters linked to her disappearance. The deadlines for two reported ransom letters, according to CNN, have since passed.

Savannah and her siblings have acknowledged the alleged existence of ransom notes and also directly addressed their mother's alleged abductor in video messages posted to social media.

Authorities have been canvassing the neighbourhood of Nancy's daughter Annie Guthrie, per CNN.

The newly released footage of a possible suspect is the biggest advancement in the investigation so far, but a suspect has still not been named.

Authorities are urging anyone with information to come forward to assist the ongoing investigation.

Blood that was found inside Nancy's home has been identified as hers.

A reward of $50,000 has been announced for information leading to Nancy's safe return or the arrest of anyone involved in her disappearance.

What did the alleged Nancy Guthrie ransom notes say?

In the days after Nancy went missing, it was reported that several media outlets had received alleged ransom notes, including TMZ and local outlets KGUN and KOLD, per CNN.

Tucson local news station KOLD's news anchor, Mary Coleman told CNN a ransom note sent to the station had "

The first reported deadline passed last Thursday, a second, set for Monday evening, has also passed, KOLD reports.

The legitimacy of the notes have not yet been confirmed.

"A lot of it is information that only someone who is holding her for ransom would know — some very sensitive information and things that people who were there when she was taken captive would know," Coleman added.

Last Thursday local time, FBI Agent Heith Janke said that while local authorities are looking into ransom notes, they had arrested one person who's accused of crafting a fake one.

"We have made one arrest related to an imposter ransom demand, and a complaint will be presented to a magistrate judge later today," Janke said, per People.

Janke warned the public anyone taking advantage of the situation would be prosecuted.

What have Nancy Guthrie's children said?

Following their initial media comments, Nancy's children — Savannah, Camron and Annie — released an Instagram video pleading for their mother's return home.

Savannah referred to Nancy as "our heart and our home", adding that the family is concerned about her wellbeing due to Nancy's health.

"She is 84 years old," Savannah said. "Her health, her heart is fragile. She lives in constant pain. She is without any medicine. She needs it to survive. She needs it not to suffer."

The children also appealed to their mother, with warm words to keep her going, should she hear the video.

"Mommy, if you are hearing this, you are a strong woman," Savannah continued.

"Everyone is looking for you, mommy, everywhere. We will not rest. Your children will not rest until we are together again.

"We speak to you every moment and we pray without ceasing and we rejoice in advance for the day that we hold you in our arms again. We love you."

The family acknowledged reports in the media of alleged ransom notes, as well as the difficulty of verifying any proof of life in the age of artificial intelligence.

"We, too, have heard the reports about a ransom letter in the media," Savannah said in the video. "As a family, we are doing everything that we can. We are ready to talk.

"However, we live in a world where voices and images are easily manipulated. We need to know without a doubt that she is alive and that you have her. We want to hear from you and we are ready to listen. Please, reach out to us."

The family have since continued to post to Savannah's Instagram account pleading for Nancy's safe return.

In another video, posted over the weekend, the siblings appear to directly address Nancy's alleged abductor, appearing to refer to a ransom.

"We've received your message and we understand. We beg you now to return our mother to us so that we can celebrate with her," Savannah said as she sat alongside her siblings.

"This is the only way we will have peace. This is very valuable to us and we will pay."

Yesterday, Savannah posted yet another video, thanking her audience for "all of the prayers" for her family.

"We believe our mum is still out there. We need your help," she added, pleading for anyone to come forward with information in what she called her family's "hour of desperation".

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A post shared by Savannah Guthrie (@savannahguthrie)

The details of the Nancy Guthrie case.

Per CNN, the latest timeline of Nancy's movements is as follows.

At about 5:32pm she travelled to visit a local family's home. They dropped her back about 9:48pm when the garage door opened. It closed two minutes later.

At 1:47am, the doorbell camera on her home disconnected. At 2:12pm software reportedly detected a person on camera but no video was available. At 2:28am her pacemaker app became disconnected from her phone.

The family checked on Nancy at 11:56am the next morning. Six minutes later, the police were called. The patrol arrived in another 12 minutes.

On February 5, the FBI, working jointly on the case with the Pima County Sheriff's Department announced a $50,000 reward for information.

According to the Associated Press, many of Nancy's belongings remained at her Tucson home, including her mobile phone, wallet, car and medication.

Although Nancy was of sound mind, officials say her limited mobility led them to believe she would not have left on her own.

"This is not dementia-related. She's as sharp as a tack," Nanos said in a press conference, per Associated Press.

"The family wants everyone to know that this isn't someone who just wandered off.

"We know she didn't just walk out of there, that we know," he added, "There are other things at the site, at the scene, that indicate that she did not leave on her own."

Nanos said that Guthrie requires daily medication, without which she may die.

"If she's alive right now, her meds are vital. I can't stress that enough. It's been [more] than 24 hours and the family tells us if she doesn't have those meds, it can become fatal," Nanos said as investigations began.

Nancy Guthrie's life in the public eye.

Nancy's daughter Savannah, who was born in Australia but raised in the US, has always spoken fondly of her mum and even invited her to join her on her morning show several times.

She's become a beloved member of the Today family.

Savannah Guthrie is pleading for prayers for her mother's safe return. Image: Instagram/ @savannahguthrie

In a post to her Instagram, Savannah referred to her mother as "a woman of deep conviction" and pleaded with those around her to pray for her mother's safe return.

"Thank you for lifting your prayers with ours for our beloved mum, our dearest Nancy, a woman of deep conviction, a good and faithful servant," she wrote. "Raise your prayers with us and believe with us that she will be lifted by them in this very moment."

"We need you," she said in a message to her mum, adding, "Bring her home."

Speaking at the press conference, Nanos echoed Savannah's sentiment.

"We have someone's life who is in jeopardy," he said. "We've got to find her and we've got to work hard to do that."

"Please help us bring Nancy Guthrie home," Tucson FBI chief, John Edwards added.

More to come.

Feature image: Instagram/savannahguthrie and FBI.