Watch: What's happened since Savannah Guthrie's mother disappeared?

Arizona police say they believe Nancy Guthrie, the missing mother of US news anchor Savannah Guthrie, "is still out there", after she disappeared from her home this weekend. Police say they have yet to identify a suspect in her disappearance.

At a media briefing on Thursday, Pima County Sheriff Chris Nanos said investigators are working under the assumption she is still alive and are "going to continue thinking that way until we find her".

Here's what has happened since the 84-year-old grandmother was reported missing on Sunday.