<p>Two people were reported killed and five others wounded in a mass shooting early Friday in Back of the Yards on the South Side.</p><p>Witnesses told police two masked men began walking down the block and opened fire on a group of people in the 5100 block of South Wood Street around 12:25 a.m., according to police reports. </p><p>The two people who were killed were both male, ages unknown. One was shot in the head, chest and a leg and was pronounced at the University of Chicago Medical Center.