Egypt's top prosecutor on Sunday named 18 Muslim Brotherhood members, including the group's leader and his deputy, as terrorists in the first implementation of an anti-terror law passed earlier this year.
In a statement, chief prosecutor Hisham Barakat said the decision follows a February court ruling that convicted Brotherhood leader Mohammed Badie; his deputy Khairat el-Shater; the head of the group's political party Saad el-Katatni and others of orchestrating violence in 2013 that killed 11 people and wounded over 90 outside their office.
The clashes were at the start of mass protests against President Mohammed Morsi, also a member of the group, and days before the military ousted him.
Badie, el-Shater and el-Katatni along with senior leaders Mohammed el-Beltagy, Essam el-Erian and nine others were sentenced to life in prison. Another four were sentenced to death. The sentences can be appealed.
But the new law, passed in February, allows prosecutors to freeze assets of the designated terrorists, barring them from public life or travel for renewable three-year periods based on the preliminary verdict and with the approval of a panel of judges.
The law also broadens the state's definition of terrorism to include anyone who threatens public order "by any means."
The law drew criticism from rights groups who charged that it expands the state arsenal of legislation empowering authorities to go after political opponents with few, if any, options to redress miscarriages of justice.
The government says it needs the law in its campaign against an expanding insurgency by militant groups, including one that has pledged allegiance to the Islamic State group fighting in Iraq and Syria. Some of these groups say they are avenging the military's ouster of Islamists from power and the subsequent crackdown on supporters.
On Sunday, a militant group known as Ajnad Misr, or "Egypt's soldiers" claimed responsibility for a bombing a day earlier in front of Cairo University that wounded eight people, including four police officers.
The group said in a statement posted on a militant website that it planted the bomb targeting police officers and private security guards at the university entrance.
The government blames the Brotherhood for the violence, saying the group is seeking to destabilize the government after Morsi's ouster.
The group denies the charges while its leaders largely languish in jail or have escaped the country to avoid the crackdown.