As the search for Savannah Guthrie's mother, Nancy, continues, a cardiologist explains how pacemakers work and if they can be used to track a missing person's location.

There has been no response to two separate pleas from “Today” show host Savannah Guthrie’s family for their mother’s apparent kidnapper to make contact.

Speaking to reporters in the Oval Office on Tuesday afternoon, President Donald Trump tells reporters that the situation is “terrible.”