Authorities searching for the missing mother of a US TV host have said they believe "she's still out there" but have no suspects.
Nancy Guthrie, 84, was last seen at her home near Tucson, Arizona, on Saturday evening after being dropped off by family.
She was reported missing the next day after she did not appear at church, and a ransom note demanding Bitcoin was sent to several media outlets.
Latest updates on missing mother
Blood belonging to Ms Guthrie - whose daughter Savannah Guthrie is co-anchor of the Today show - was found in the porch area.
Her family have released a video pleading with whoever might have her to get in touch and provide proof she is alive.
The FBI said on Thursday that no further contact had been made since the ransom note was sent - as it also announced a $50,000 (£37,000) reward.
Local sheriff Chris Nanos told reporters the case was being treated as kidnapping but said they hadn't yet identified any suspects.
However, he said he believes Ms Guthrie - who needs daily medication - "is still out there".
There were several cameras at her home including a doorbell cam, and one detected movement at 2.12am, but the sheriff said they hadn't been able to retrieve the footage.
Ms Guthrie's pacemaker app also disconnected from her phone at 2.28am, the sheriff added.
The ransom note gave a 5pm deadline (midnight UK time) on Thursday for payment to be made, and a second deadline on Monday, said lead FBI agent Heith Janke.
Mr Janke urged the perpetrator to change course and let Ms Guthrie go.
"This is an 84-year-old grandma that needs vital medication for her well-being. You still have the time to do the right thing before this becomes a much worse scenario for you. Please return Nancy home," he urged.
'We need to know she's alive'
The huge publicity over the case in the US has also caught Donald Trump's attention.
The president said on Truth Social that he had spoken to Savannah Guthrie and directed all federal law enforcement to be available.
The Guthrie family's video, recorded with FBI assistance, spoke directly to the kidnapper.
It urged: "We are ready to talk... 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."
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Flanked by her sister and brother, a tearful Savannah Guthrie added: "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.
"Mummy, if you are hearing this, you are a strong woman. You are God's precious daughter."
The amount demanded in the note has not been disclosed and FBI agent Mr Janke said any decision on whether to pay is "ultimately decided by the family".
He added that agents had also arrested a "total imposter" on Thursday morning who had sent a ransom note and was looking to profit from the case.
(c) Sky News 2026: 'Kidnapped' mum of TV host 'still out there', authorities believe
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