BONNEVILLE COUNTY -- Deputies with the Bonneville County Sheriff's Office are investigating a report that someone spotted a triple-homicide suspect who is currently the subject of a nationwide manhunt.

The sighting of 60-year-old Gerald "Mike" Bullinger was reported Thursday in the Fall Creek area near Swan Valley. Investigators searched the area, but did not find Bullinger.

According to the sheriff, it's not confirmed that the subject of the report is actually Bullinger.

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The search for Bullinger, a commercial pilot, began last week after the bodies of two women and a teenage girl were found at his house on KCID Road in Caldwell. All three victims had been shot to death and their bodies hidden in a shed on the property.

One of the victims has been identified as Bullinger's wife, 56-year-old Cheryl Baker. The other two have not yet been officially identified, but friends suspect they are 48-year-old Nadja Medley and her 14-year-old daughter Peyton, who had recently moved from Utah to live with Bullinger in the house on KCID Road.

Nadja Medley and Bullinger had been dating for two years, friends say. It's unclear whether either his wife or his girlfriend was aware of the other's existence.

The car Bullinger had been driving - a white Ford Focus registered to his wife - was discovered in Wyoming July 12. The vehicle was parked at a remote campground in the the Bridger-Teton National Forest, near the border with the Grand Teton National Park.

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Authorities believe the car had been there for weeks before it was discovered, and it is unclear whether Bullinger is still in that area.

The Federal Bureau of Investigation and local law enforcement has been combing the area with live-search and cadaver dogs, but have not found the fugitive.

Deputies in Bonneville County are continuing to monitor the area where the sighting was reported. The sheriff's office has asked residents to immediately report any suspicious activity to dispatch at 208-529-1200.

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Bullinger is considered armed and dangerous. Anyone who spots him should call 911.