Judge Barry Williams announced a hung jury Wednesday after three days of deliberation didn't yield a decision from the jury.

Williams said the jurors had "clearly been diligent" before he dismissed them.

Porter, 26, faced charges of involuntary manslaughter, second-degree assault, reckless endangerment and misconduct in office after the death of Gray in Baltimore in April.

That same day, Williams ordered the panel members to continue deliberating.

A jury must be unanimous in order to reach a verdict on any charge.

A week after his death, in the midst of national protests against police brutality, Gray's funeral prompted intense rioting and looting in the Baltimore.

Porter is the first of six officers charged in Gray's death. If convicted, Porter could face more than 10 years in prison. A mistrial allows for Porter to be retried. The five other officers will be tried individually in 2016.