Police say a white man with a history of racial provocations and confrontations with police ambushed and fatally shot two white officers. The separate attacks happened early Wednesday in the Des Moines, area. The suspect identified as 46-year-old Scott Michael Greene surrendered hours later.

The two police officers shot and killed in separate ambush-style attacks are being remembered as friendly public servants. Des Moines police Sgt. Tony Beminio was a dedicated and popular officer who seemed to always have a smile. Urbandale officer Justin Martin is recalled as a “kind, gentle, compassionate” person who was just beginning a law enforcement career.

A man says he had two recent confrontations with the man police believe ambushed and fatally shot two Des Moines-area police officers. Ardis Gardner, who is black, says Scott Michael Greene, who is white, waved a Confederate flag during the national anthem at the group of black parents he was sitting with at an Oct. 14 high school football game and intimidated them again a week later at another game.