FBI An image of the suspect in the kidnapping of Nancy Guthrie - a person is seen close up in black and white, wearing a balaclava and holding an obscured item in their left hand, which we can see has a black glove covering it FBI
The FBI has now confirmed that the masked man seen in the video is a suspect in the case
The FBI has released the first physical description of the man believed to have kidnapped Nancy Guthrie, the mother of US news anchor Savannah Guthrie.
Nancy Guthrie, 84, disappeared in the middle of night from her Tucson, Arizona home and was last seen two weeks ago. The authorities believe she was taken against her will.
The FBI has analysed footage from a doorbell camera outside her home and believes she was kidnapped by a male who is between 5ft 9in and 5ft 10in (175-177cm) tall with an average build.
It is first time the man in the video has been officially identified as a suspect in the case, which has drawn a huge amount of attention both in the US and abroad.
The FBI said in its latest statement that it had been able to establish identifying details after carrying out a forensic analysis.
It highlighted the backpack being worn by the suspect in the video, which was released earlier this week and identified it is a 25-litre Ozark Trail Hiker Pack.
A pair of black gloves has also been found during the search for Guthrie, the BBC's US broadcast partner CBS reported on Thursday.
FBI An Ozark Trail Hiker backpack, the type which police believe was used by the suspectFBI
Nancy Guthrie was last seen on the evening of 31 January when family members dropped her home. Members of her church noticed her absence the following day and notified her family.
Officials have warned that she may be in dire health without her medication. Pima County Sheriff Chris Nanos said she was "not in good physical health" but had no reported cognitive issues.
Since 1 February, the FBI said it had received more than 13,000 tips in relation to the case - including 4,000 in the 24 hours after the doorbell camera footage was released.
It has now doubled the reward for information about Guthrie's disappearance from $50,000 (£36,700) to $100,000.
Getty Images Savannah Guthrie smiling widely with a vibrant orange sleeveless blouse and a bright orange and yellow pattern skirt, standing next to her mother in the Today studio. Nancy is smiling, wearing a necklace, and wearing a blue top. Getty Images
The reward for information related to the disappearance of Nancy Guthrie (right) has increased to $100,000
Earlier this week, a man was detained in connection with Guthrie's disappearance and his home in Rio Rico - south of Tucson - was searched before he was released.
He told reporters he did not know who Nancy Guthrie was.
Savannah Guthrie and her two siblings have released a number of social media pleas directed at their mother's potential abductors.
They believe she is still alive and have indicated they would be willing to pay for her return.
'Mum is still out there' - Savannah Guthrie issues new plea as ransom deadline passes
Officials investigate DNA found in Nancy Guthrie's home
The sheriff's department says it is working to identify who the DNA belongs to, but would not disclose where it was found.