The violent chain of events began when sergeant Mark Dunakin and Officer John Hege, stopped a driver. That driver then shot them.
PHOTOS: Bay Area police officers shot, killed over past decade
[Ads /]
Two SWAT team members, Sergeants Ervin Romans and Daniel Sakai died following a shootout with the suspect.
Police motorcycles lined 82nd Avenue outside St. Benedict Catholic Church where people reflected on the lives lost in 2009.
[Ads /]
"Irv, Dan, Dunny, Hege we miss you beyond what words can express. We will always remember you and the many ways you made us smile, laugh, live, and love," said Pastor and Police Chaplain Jayson Landeza.
Other SWAT officers eventually shot and killed the man suspected of murdering the four officers.