January 19, 2017 5:40 pm Preview: Heartbroken Mom Speaks out on Son's Murder See Ruth’s full story Sunday on This is New England US & World Videos 3:05 100 protesters detained at Northeastern University 2:39 Community mourns police sergeant killed on duty 2:50 Community mourns Billerica police sergeant killed on duty 4:32 Anti-war protester at Northeastern speaks amid arrests: ‘We are peaceful students' 10:42 Multiple people arrested as police clear campus encampments