Denver Police Chief Robert White talks to reporters Monday, March 16, 2015 about four shooting deaths in the city over the weekend.

(Photo: CPR/Megan Verlee)

Denver police confirmed Monday afternoon that three homicides this past weekend were gang related, a reflection of  gang tensions that have been simmering in the city since last November, when a shooting at a nightclub near Sports Authority Field left a popular local rapper dead and others injured.

Denver Police Chief Robert White is urging anyone who knows anything about this weekend’s murders to call in a tip. "We’ve got to be much more aggressive in fighting some of the gang activity that we’re seeing, and that needs to happen collaboratively," he says, adding that people who could help the investigations are not working with police.