The Costa Mesa woman who was kidnapped from an African wildlife park earlier this week has still not been located.
Authorities report the search has intensified and "hard negotiations" are taking place for the release of the two hostages.
Kimberly Sue Endicott and her local driver, Jean-Paul Mirgene Remezo, were taken at gunpoint by four armed men inside Queen Elizabeth National Park in Uganda Tuesday evening.
The hostage-takers have repeatedly made demands for a $500,000 ransom since that horrible day.
CBS News reports the search for Endicott and her tour driver has expanded beyond the park.
"The joint security teams have cut off all exit areas on the border between Uganda and the DRC (Democratic Republic of the Congo) in search for the victims, especially because the park is at the border," said Uganda deputy police spokesperson Polly Namaye.
The kidnappers have reportedly been using Endicott's phone to negotiate her release and that she has been on the phone at least once a day to prove she is still alive.
The entire southern portion of the park is closed to tourists as Ugandan military forces carry out a full "sweep" of the area, CBS News reports.
The U.S. Embassy has warned Americans in the area to be careful as the northern part of the park remains open.
Tourism operators say cancellations are already flooding in.
Recognized kidnap expert Dr. Frank Grimm joined the show Friday with more information on how the U.S. goes about getting an international kidnapping victim back. Listen to his interview below.
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