Officials with the Tamaulipas Attorney General's Office spoke to Action 4 News about the murder and decapitation of the lead investigator with the David Hartley case.
The head of Tamaulipas State Police Commander Rolando Armando Flores-Villegas was dropped off in a suitcase at a Mexican army post in Miguel Aleman on Tuesday morning.
Ruben Dario-Rios with the Tamauilpas Attorney General's Office said Flores-Villegas was killed due to an investigation that had nothing to do with the Hartley case but rather another investigation that he said he could not discuss.
No suspects have been publically named and no arrests have been made in the death of the slain police commander.
Dario-Rios said Flores-Villegas was a veteran law enforcement officials with the Tamaulipas State Police.
He added that Commander Flores-Villegas was part of a team looking Mexican side into for the body of David Hartley.
All the members of the search crew returned home on Monday night except for Flores-Villegas.
Zapata County Sheriff Sigifredo Gonzalez said authorities are expressing their condolences.
"We're said to say that the family of the individual who was killed will be without a husband...without a father when all he was doing was trying to help find the body of Mr. Hartley," Gonzalez said.
Hartley has been missing since September 30th when he and his wife Tiffany Hartley were ambushed by armed men while visiting the flooded ruins of Guerrero Viejo on the Mexican side of Falcon Lake.
Tiffany Hartley told authorities that David was shot in the head but she managed to escape and make back to the American side of the lake.
Mexican authorities have vowed that the search will continue but the search has proven dangerous and deadly.
Six alleged gunmen with a drug trafficking organization were killed in a firefight the soldiers last Thursday afte a Mexican military aircraft spotted them in brushy area.
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