TUCSON, Ariz. — Four months after Nancy Guthrie vanished from her home in the Catalina Foothills area near Tucson, the high-profile disappearance of the 84-year-old mother of NBC "Today" co-anchor Savannah Guthrie remains unsolved, with authorities treating it as a suspected abduction and homicide.

A $1 million reward offered by the family for information leading to her safe return or the arrest and conviction of those responsible has generated thousands of tips, yet no arrests have been made and her body has not been recovered. Here is a 10-point timeline summarizing key developments in the case so far.

January 31-February 1: Last Seen and Initial Evidence Nancy Guthrie was last seen on January 31 after a family dinner. On February 1, she disappeared from her residence. Blood evidence matching her DNA was found on the porch, along with signs of a possible struggle. A masked individual was captured on doorbell camera footage tampering with the camera shortly before the disappearance.

Early February: Law Enforcement Response The Pima County Sheriff's Office launched an investigation, joined by the FBI, Customs and Border Protection and search-and-rescue teams. Multiple searches of the surrounding desert terrain began immediately using cadaver dogs, drones and ground teams. A $1 million reward was announced.

February 24: Savannah Guthrie's First Public Appeal Savannah Guthrie posted an emotional video on Instagram, saying, "Every hour and minute and second and every long night has been agony." She added, "Worrying about her, and fearing for her, and aching for her, and most of all just missing her," while urging the public to........

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