The severed head of a Mexican police commander reported to be investigating an alleged pirate attack on Falcon Lake was delivered to the Mexican military, sources said Tuesday.Drug Thugs Decapitate Mexican Police Commander Investigating Lake Pirates Killing

According to the Associated Press, U.S. and Mexican authorities have confirmed that Commander Rolando Flores, the head of state investigators in the border city of Ciudad Miguel Aleman, had been killed. Flores was actively investigating the mysterious disappearance of American tourist David Hartley while he and his wife, Tiffany, visited Falcon Lake on Sept. 30. According to Tiffany Hartley, David was shot and presumably fell into the lake, however search and rescue officials have yet to turn up the missing man’s body.

Ruben Rios, a spokesman for the Tamaulipas state prosecutor’s office says the grizzly murder of Commander Flores appears unrelated to the Hartley investigation, but U.S. authorities have warned against threats of violence from drug gangs who control much of the area.

In an interview with the Houston Chronicle, state Rep. Aaron Pena, D-Edinburg, said he was told the severed head was delivered to military officials in a suitcase to an area near Miguel Aleman, a small city directly across the border from Roma, Texas.

According to the Chronicle, this area of the border territory is known to be under the control of the so-called Zeta drug cartel, a group which “fiercely protects the remotely populated ranchland lining the Texas-Mexico border, as well as the Mexican side of the vast Falcon Lake reservoir.”

Flores’ investigators of the Hartley disappearance had been hampered by the threat of violence from the group and individual investigators have expressed fears of searching in Zeta turf.

Glenn took an in-depth look at the Zeta group in 2007:

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