Joanna Dennehy told the judge as she pleaded guilty to murdering three men , "I've pleaded guilty and that's that".
Dennehy also admitted "preventing the lawful and decent burial" of all three murder victims.
Her shock guilty pleas left the courtroom at the Old Bailey stunned.
The defendant's barrister, Nigel Lickley QC, said: "The course of the arraignment is not one we had anticipated."
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