Savannah Guthrie, co-host of the "Today" show, posted a throwback video of her mother, Nancy, as well as a family picture, as the search for the 84-year-old continues.The video is captioned, "Our lovely mom. We will never give u p on her. Thank you for your prayers and hope." View this post on Instagram A post shared by Savannah Guthrie (@savannahguthrie) Nancy Guthrie was last seen on Jan. 31. She was reported missing the next day after he family could not get in contact with her.Authorities believe she was taken from her Tucson-area home against her will.On Thursday, authorities were seen putting up a white tent near her front door. DNA testing previously confirmed that the blood found on Nancy Guthries front porch belonged to the 84-year-old. Tent goes up outside Nancy Guthrie's homeThe Pima County Sheriffs Office said it issued a neighborhood alert asking residents to submit any video recorded within a 2-mile radius of Nancy Guthries home between Jan. 1 and Feb. 2 that could assist in the investigation.Meanwhile, authorities continue to follow up on thousands of leads, including alleged ransom notes. However, a suspect or person of interest has still not been identified.On Tuesday, the FBI released videos and images of a masked individual outside Nancy Guthrie's home on the morning she disappeared. The individual, who is armed, is seen walking up to the front door and trying to cover the doorbell camera. The sheriffs office said investigators recovered several items of evidence, including gloves, which are being submitted for analysis to determine whether they were worn by the masked individual.Authorities are offering a $50,000 reward for information leading to the resolution of the case. ...read more read less