CIUDAD JUAREZ, Mexico (AFP) - A judge in northern Mexico charged four teenagers and one child with homicide over the torture and gruesome killing of a six-year-old during a "kidnapping game" that has shocked the country.

The two 15-year-old boys, two 13-year-old girls and one 11-year-old boy attended the court hearing in the state of Chihuahua, a week after the murder of Christopher Raymundo Marquez.

He was found buried under a dead dog and weeds next to a stream on the outskirts of the state's capital on May 14. Prosecutors said the children had tied him up, nearly asphyxiated him, stoned him and stabbed him.

The judge, Francisco de Leon Merino, ordered that the 15-year-old boys be jailed in the Chihuahua Court for Minors while the three younger ones be kept under the custody of the state child services agency.

The case has raised questions about the influence of Mexico's relentless drug war on young minds after tens of thousands of people have been killed since 2006.