Jessica Alba is outraged Casey Anthony has been cleared of murdering her daughter.

The American actress has branded the decision "revolting" after the Florida mother was found not guilty of taking the life of her young daughter Caylee following a 10-hour deliberation by an Orlando courtroom jury.

Following the verdict, the 30-year-old brunette wrote on twitter: "Following the Casey Anthony trial was nauseating but the verdict is revolting."

New mother Christine Applegate and 'Karate Kid' actor Ralph Macchio were also shocked by the outcome of the trial - which saw Anthony accused of drugging and suffocating her two-year-old daughter with duct tape in 2008 - and American socialite Kim Kardashian was "speechless" at the jury's decision.

She tweeted: "WHAT!!!!???!!!! CASEY ANTHONY FOUND NOT GUILTY!!!! I am speechless!!!"

Motley Crue bassist Nikki Sixx also took to the social networking site to explain his disbelief at the not guilty verdict.

He wrote on twitter: "I am ashamed and shocked that our legal system failed us and found Casey Anthony not guilty for killing her daughter or any other charges."