Published: Mar 07, 2012 4:45 PM EST

WEST PALM BEACH, Fla. (AP) - The father of three children killed in 2010 is suing child welfare officials he says were negligent.
    
Michael Barnett has filed the lawsuit against the Department of Children and Families in the Riviera Beach shooting spree by his ex-wife's estranged husband. The Palm Beach Post (http://bit.ly/y6YaIe) reports it comes a month after a man who was the father of a fourth slain child filed similar litigation.
    
Barnett claims DCF ignored obvious warning signs, including dozens of visits to the house by police and the agency's own investigation sparked by threats and ongoing violence.
    
Police say Patrick Dell fatally shot four stepchildren and their mother before killing himself. A fifth stepchild was shot but survived.
    
A DCF spokesman did not immediately return a call Wednesday seeking comment.

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