Police activity under way near Nancy Guthrie's home

Police activity connected to the search for Nancy Guthrie, the missing mother of US news anchor Savannah Guthrie, is under way at a residence about two miles from her home.

Armed police teams have been seen coming in and going from the area, with a sheriff's vehicle blocking the road.

It comes after local officials said investigators had found DNA at Guthrie's address which does not belong to her or anyone close to her.

The 84-year-old disappeared in the middle of night from her home in Tucson, Arizona, nearly two weeks ago. Authorities believe she was taken against her will.

In a social media post, the sheriff's department said "law enforcement activity" was ongoing "related to the Guthrie case" without providing further details.

Pima County Sheriff Chris Nanos told local media outlet KOLD that investigators were "actively working a lead", the BBC's US news partner CBS reported.

More than a dozen law enforcement vehicles, both marked and unmarked, have been seen in the area by BBC News, including Swat teams and forensics.

Investigators have also found several gloves, with the closest discovered about two miles from Nancy Guthrie's home.

The sheriff's department said reports that a glove was found inside her home or on the property are inaccurate.

All collected evidence has been sent for laboratory analysis, they added.

It said investigators had been able to establish identifying details about the suspect after analysing footage from a doorbell camera outside Guthrie's home.

The suspect was wearing a 25-litre Ozark Trail Hiker Pack backpack in the footage, the FBI said.

After the doorbell footage was released, investigators received more than 13,000 tips, including 4,000 in the 24 hours.

The FBI has also increased the reward for information about Guthrie's disappearance from $50,000 (£36,700) to $100,000.

The county sheriff department said the suspect description "remains a key focus", adding: "However, investigators are not ruling out any individuals or possibilities."

Investigators have also issued a wider appeal for video footage from Guthrie's neighbours.

Police have said Nancy Guthrie, 84, needs daily medication and has limited mobility.

Savannah Guthrie and her two siblings have released a number of social media pleas directed at their mother's abductor.

They believe she is still alive and have indicated they would be willing to pay for her safe return.