US TV show host Savannah Guthrie has addressed her mother’s alleged kidnappers in an emotional video, saying the family is ready to talk.

In a video posted to Instagram on Thursday afternoon AEST, the NBC Today show host read from a statement alongside her sister Annie and her brother Camron.

She said her family were aware of reports about a ransom letter sent to at least two media outlets however needed proof from the kidnapper’s that her mother Nancy Guthrie was still alive.

“We live in a world where voices and images are easily manipulated,” Savannah said.

“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.”

On Wednesday, a ransom note was sent to news outlet TMZ demanding millions of dollars in Bitcoin.

Pima County Sheriff Chris Nanos confirmed the department had received more than one ransom note.

The FBI has shared a ransom note with Savannah, although Nanos did not confirm whether it was the same note sent to TMZ.

In the video Savannah also thanked the public for “the prayers for our beloved mum“.

“We feel them and we continue to believe that she feels them too,” she said.

Savannah described her mother as a “kind, faithful, loyal, fiercely loving woman of goodness and light” and a person who is “funny, spunky and clever.”

“She has grandchildren that adore her and crowd around her and cover her with kisses,” she said.

“She loves fun and adventure. She is a devoted friend. She is full of kindness and knowledge. Talk to her, and you’ll see.”

The TV host said her mother’s health and heart are fragile.

“She lives in constant pain. She is without any medicine. She needs it to survive and she needs it not to suffer.”

In the closing seconds of the video Savannah spoke directly to her mother saying: “Mummy, if you are hearing this, you are a strong woman, you are God’s precious daughter Nancy.”

Authorities have said they believe Nancy is still alive.

Nancy was last seen alive on Saturday (US time) and was reported missing the following day by family members after she failed to attend church.

Despite speculation online, the sheriff’s department has confirmed there is no suspect in the case, including claims her son-in-law, Tommaso Cioni, may be involved.

“We have not identified a suspect or person of interest in this case. Detectives continue to speak with anyone who may have had contact with Mrs Guthrie. We are also awaiting additional forensic results,” the department said in a statement to TMZ.

Cioni became a focus of public speculation after police searched his vehicle.

Two senior officials briefed on the investigation told NBC News that investigators are probing what appears to be blood found outside Nancy’s home.

The officials said Nancy’s pacemaker appears to have disconnected from its monitoring app early Sunday.

– With NBC