CANYON COUNTY (KTVB) -- A Notus man tested positive for drugs after a fatal crash that killed an elderly Parma couple last year, according to Idaho State Police.

Twenty-six-year-old Spook Meras was charged with two counts of manslaughter and two counts of injury to a child Monday. The charges come more than a year after the May 3, 2014 head-on wreck on Highway 20 near Purple Sage Road.

A passenger in the car that was hit, 74-year-old Tillie Montoya, died in the crash. Her husband, 74-year-old Eloy Montoya, succumbed to his injuries several weeks later.

Two children in Meras' car were also hurt in the wreck. Police say a boy fractured his leg and suffered a broken trachea and bruised lung, while a girl in the vehicle was less seriously injured.

According to court documents, Meras told Idaho State Police Cpl. Brandon Bake that he had been working long hours and had fallen asleep behind the wheel just before colliding with the Montoyas' car. But Meras also told police that he had smoked methamphetamine and marijuana a day and a half before the wreck, and would likely fail the drug test, according to Bake's report.

Meras tested positive for amphetamine, methamphetamine, Midazolam, Propofol and marijuana. Midazolam and Propofol are anesthetics commonly used before surgery to render someone unconscious. It is not clear whether Meras took the anesthetics before the wreck or whether he was given them legally at the hospital as treatment.

A warrant was issued for Meras' arrest in the case in late April.

Meras is due back in court May 21 for a preliminary hearing.