TUCSON, Ariz. — Authorities are intensifying their search for Nancy Guthrie, the 84-year-old mother of NBC's 'Today' show host Savannah Guthrie, who was reported missing on February 1. Late Friday night, law enforcement officials deployed roadblocks about two miles from her home in Tucson as part of the investigation.

A heavy presence of sheriff's and FBI vehicles, including forensics teams, was noted at the scene. Although the Pima County Sheriff's Department confirmed that these actions are related to the investigation, they refrained from disclosing further details.

Authorities are particularly worried for Nancy's health as she requires daily medication and has previously dealt with medical issues, including high blood pressure and a pacemaker.

Evidence collected have heightened the alarm—the presence of blood on her front porch has raised serious concerns, while ransom notes allegedly sent to news outlets have also been discovered, with two deadlines for payment having long passed.

Investigators are sifting through thousands of leads, with the FBI reporting over 13,000 tips received since the inception of the case. Meanwhile, the sheriff’s department notes they’ve fielded more than 18,000 calls from the public regarding the situation.

Recent developments include the release of surveillance footage showing a masked suspect outside Guthrie's home just before her disappearance. Experts assert that this video may contain significant clues that could assist investigators in uncovering what happened on that fateful night.

As the investigation unfolds, authorities remain committed to finding Nancy Guthrie, hoping that new leads will emerge and that the community can help bring her home safely.