Kentwood police investigate a stabbing that occurred at a playground in Pinebrook Village. Picture: Joel Bissell, The Grand Rapids Press

Grand Rapids, Michigan -

A 12-year-old boy has been charged with murder in the fatal stabbing of a nine-year-old boy at a playground in western Michigan.

The boy pleaded not guilty during an arraignment hearing in Grand Rapids on Tuesday, a day after the attack in nearby Kentwood.

Witnesses say the 12-year-old went to a nearby home after the stabbing, called police and calmly turned himself in, then tried to flag down officers when they arrived.

The victim, Michael Conner Verkerke, ran to his home and collapsed. Police say he later died at a hospital.

Defence attorney Charles Boekeloo says he entered the plea for the boy and may seek a mental evaluation to determine if he's competent to stand trial.

The boy was ordered held without bond in a juvenile detention centre. - Sapa-AP