Winnetka shooting a lightning strike

While the LAPD so far this year has continued to build on the momentum from last year's drops in San Fernando Valley crime, last week's quadruple homicide and SWAT team shooting in Winnetka underscores the sometimes random nature of violence and law enforcement's limited ability to prevent it. Rick Coca in the Daily News.

Although police say Edwin Rivera began to have mental health issues following the death of his mother a decade ago, family and friends say there was no indication he would ever turn so violent, killing three family members and Officer Randal Simmons and severely wounding Officer James Veenstra.

"This is like a lightning strike," LAPD Detective Joel Price said. "How are you going to prevent something like this from happening?