Egypt's top prosecutor ordered on Monday challenging a verdict dropping charges against toppled President Hosni Mubarak, his Interior Minister Habib al-Adly and six of his aides over complicity in the killing of protesters during the January 2011 uprising.
Prosecutor General Hisham Barakat said in a statement that he mandated a team of the prosecution's technical committee to study the verdict, which came out on Saturday, sparking wide anger.
The study revealed that the verdict is "legally flawed", the statement read.
The court has also acquitted Mubarak and Egyptian businessman Hussein Salem of the graft charges related to the exportation of gas to Israel. Salem is being tried in absentia.
Mubarak and his two sons Alaa and Gamal were accused of exploiting their influence in Salem's favour after the latter granted them five villas in the Sinai resort city of Sharm el-Sheikh. The judge heading the trial, Mahmoud al-Rashidi said that the statute of limitations in this case has expired, and therefore the court lacks jurisdiction to rule on it.
The two court ruling will also be challenged by the prosecution.
Mubarak and his interior minister were sentenced to life in prison in 2012 for the same charges before an appeals court ordered their retrial. The retrial began in April, 2013.
In May, a Cairo court sentenced Mubarak to three years in prison on embezzlement charges.
He is serving time in a military hospital in Cairo, where he returned upon Saturday's ruling.