Charges against a former New Mexico police officer have been increased to second-degree murder

Christopher Smelser allegedly used a vascular neck restraint on Antonio Valenzuela during a traffic stop.

(CNN)Charges against a former Las Cruces, New Mexico, police officer accused of killing a man in custody have been increased to second-degree murder from involuntary manslaughter, according to a news release from New Mexico Attorney General Hector Balderas.

Balderas also announced the attorney general's office has taken over the prosecution of the former officer, Christopher Smelser, at the request of the Third Judicial District Attorney's Office, the release stated.
CNN attempts to contact Smelser's lawyer have gone unanswered.
      Last month, when Smelser was first charged with involuntary manslaughter, his attorney, Amy Orlando, told CNN that Smelser "used a maneuver that was sanctioned by the Las Cruces Police Department during a violent struggle while attempting to take Mr. Valenzuela into custody."
        "Office Smelser regrets the outcome of the incident, however, Mr. Valenzuela had a felony warrant, ran from the police, was under the influence of drugs, had drugs on his person, had a weapon, actively resisted, and violently fought the officers," Orlando said.
          Smelser allegedly used a vascular neck restraint on Antonio Valenzuela during a traffic stop last February. Police body camera footage shows a struggle involving Valenzuela, who died after Smelser was heard saying, "I'm going to f**king choke you out, bro."
          Officers pulled over Valenzuela for a traffic stop and learned he had a warrant for a parole violation, according to a news release from the Doña Ana County District Attorney's Office.
          Valenzuela fled on foot and police chased him and deployed their Taser twice "without affecting" him, according to the district attorney's news release.
          Body camera footage released by authorities appears to show Smelser tackling Valenzuela.
          "Valenzuela was continually struggling to get away," the Doña Ana County DA's Office said. "Once on the ground, during this struggle, Officer Smelser applied a vascular neck restraint technique to gain control."
            The city informed Smelser in June of its intent to fire him, around the same time he was charged with involuntary manslaughter.
            Since Valenzuela's death, the Las Cruces Police Department has banned the use of vascular neck restraints in apprehensions.