NEW : Presidential spokesman promises investigation of police who beat protester . The latest spate of violence started during demonstrations last week to mark the two-year anniversary of the Egyptian revolution . Saturday 's matches are the first since last year 's deadly football riot . 74 people were killed after a Port Said team beat a Cairo team in 2012 . Comment: 21 Port Said residents to death for their roles in the riot .
NEW : Presidential spokesman promises investigation of police who beat protester . Saturday 's matches are the first since last year 's deadly football riot . 74 people were killed after a Port Said team beat a Cairo team in 2012 . Comment: 21 Port Said residents to death for their roles in the riot .