Paranormal investigators featured on a hit reality TV show died following a hostage standoff with police in Nevada, police said Thursday.
The Sparks Police Department identified Mark Constantino and his estranged wife Debby Constantino — who appeared on the Travel Channel's "Ghost Adventures" series — as the victims in Tuesday afternoon's incident in Sparks.
Zak Bagans, host of Ghost Adventures, called it a "dark day" while a friend of Debby Constantino posted from the couple's Twitter account urging people to speak out against domestic abuse.
The standoff unfolded in response to an investigation in neighboring Reno involving the shooting death of another man earlier on Tuesday.
Officers looking into that case determined one of the deceased man's roommates, Debby Constantino, was missing, according to NBC News station KRNV. Police tracked Debby Constantino's cellphone and found her inside an apartment in Sparks with Mark Constantino, KRNV reported.
The Sparks Police Department told NBC News that SWAT teams deployed to the apartment, evacuated neighbors and locked down the surrounding area.
Officers knocked on the door and heard several shots fired, Reno Police Department's deputy chief Tom Robinson told NBC News station KRNV.
A man inside told police "give me 15 minutes to gather my thoughts or I'll kill her," Robinson told the station, adding that police negotiators later tried to talk to the man.
After a three hour standoff, the SWAT teams deployed stun grenades known as flash bangs and entered the apartment to find Mark and Debby Constantino dead inside, the Sparks Police Department said.
Mark Constantino had recently been charged with kidnapping and domestic related charges and there had been a protection order in effect for Debby, the department added.
It said the Constantino case and Reno shooting death appear to be related, adding that no arrests have yet been made and the investigation is ongoing.