Jorge Fernandez, a criminologist whose wife and one-year-old son lived with him in Ciudad Victoria, in northern Mexico, was charged with culpable homicide over her killing. A judge jailed him for two years pending trial.
Fernandez, 34, told police he was driving home from the beach on July 2nd with his wife, Maria del Pilar Garrido, and their son when gunmen forced them to stop the car and kidnapped Garrido, also 34.
But he was arrested Tuesday after investigators detected inconsistencies in his story, Tamaulipas state prosecutor Irving Barrios told the press.
It was never clear why the kidnappers would have left Fernandez and his son alone, and no ransom demand was ever received.
Garrido's body was found on July 26th, near the spot where she was supposedly abducted.
Garrido had lived for the past three years with Fernandez in Tamaulipas, one of the states hardest hit by drug cartel violence in Mexico.
But "organized crime groups have no history of operating in this way in the region," Barrios told Mexican TV network Televisa.
He said friends and neighbors had told investigators that Garrido planned to return to Spain with her son because she feared the high crime rate in Tamaulipas.
Fernandez denies killing his wife, and her family also say they believe he is innocent.
"There are still many doubts about who committed this homicide," Fernandez's lawyer Martin Lozano told journalists.