Boston April 3, 2019 6:01 pm City Officials Unveil 2019 Boston Marathon Security Plan City officials unveiled their public safety and security plans Wednesday for the 123rd Boston Marathon. 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