The Purple Rain hitmaker has dedicated a track to those embroiled in the violent protests which erupted following the death of 25-year-old Freddie Gray, who suffered fatal injuries in police custody last week (ends26Apr15).

Prince's new song is said to address Gray's death and the unrest, during which angry citizens have looted stores, set fires and clashed with cops.

A spokesperson for the singer tells the track is a "tribute to all of the people of the city of Baltimore" and was recorded at Paisley Park Studios, the star's Minnesota recording complex, this week.

The artwork for the single has been released and features a simplistic cartoon image of Prince.