CHICAGO, April 22 (Xinhua) -- U.S. civil right activist Al Sharpton on Friday demanded a federal investigation into the fatal shooting of Patrick Lyoya, at the 26-year-old black man's funeral in Grand Rapids in the U.S. state of Michigan, the Detroit News reported.

       Lyoya was killed by a police officer on April 4 during a traffic stop. According to videos released by Grand Rapids police, the officer asked for Lyoya's driver's license, and Lyoya eventually fled the car and a chase on foot ensued. The two men ended up struggling over the officer's stun gun before the officer shot Lyoya in the back of the head.

       During the eulogy, Sharpton addressed the officer and questioned his decisions: "You turned a traffic stop into what appears on tape to be an execution." Sharpton pointed out that Lyoya was killed on the 54th anniversary of Martin Luther King Jr.'s 1968 assassination.

       Sharpton also criticized Grand Rapids police's decision to withhold the name of the officer who fatally shot Lyoya unless he is charged with a crime, local media reported.

       An autopsy found that the cause of Lyoya's death was a bullet shot to the back of the head. The Michigan State Police is investigating the shooting death.

       Hundreds of mourners attended Lyoya's funeral, reports said.