The prosecutor-general has ordered an appeal against a court verdict that dropped charges of killing protesters during the 2011 uprising against ousted president Hosni Mubarak, and acquitted him of corruption charges.
In a statement issued on Tuesday, Hisham Barakat said a committee of prosecutors had concluded that the verdict had a "legal flaw."
Under Egyptian law all the necessary appeal documents must be submitted with the Court of Cassation within 60 days of the verdict.
On Saturday, a criminal court dropped the charges against Mubarak over his complicity in the murder of protesters during the January 2011 uprising.
The judge said he would drop the murder case against Mubarak because the prosecution's earlier decision on 23 March 2011 to charge the 86-year-old lacked the legal basis to bring a criminal case against him.
Meanwhile, former interior minister Habib El-Adly, along with his six aides, were acquitted of murder and attempted murder related to the killing of protesters in 2011.
The general-prosecutor will appeal against them too.
The court also ruled that the statute of limitations had expired on the charges against Mubarak, his two sons and businessman Hussein Salem, on charges of profiteering from illegal gifts of villas.
In addition, Mubarak was acquitted of collaborating with his minister of petroleum to profit from Hussein Salem's company by giving Salem the rights to export Egyptian natural gas to Israel at below market rates.
Salem was also acquitted of the charges.
Mubarak was convicted last May of embezzling public funds allocated annually for the upkeep of presidential palaces. He received a three-year prison sentence.
While Mubarak's supporters hailed Saturday's verdict, many of his opponents expressed their anger, with hundreds protesting in Tahrir Square, the epicentre of an 18-day uprising in 2011 that ended the autocrat's 30-year reign.
Police dispersed the protests and two people were killed in clashes.
Revolutionary groups, in addition to Islamist forces, have vowed to demonstrate this week against the court's ruling. Students have already staged protests in campuses against the verdict.
It unclear yet whether and when Mubarak will be set free. The prosecution said on Monday it would issue a decision on the matter within 48 hours. It said it is calculating the period Mubarak has spent in preventative detention in order to deduct it from his 'presidential palace' sentence, according to Egyptian law.