In a video titled " retaliation is alive " , the group said it had carried out eight attacks in Cairo from 20 November 2013 , AFP reported .
They also said it would launch a new attack as revenge for abuses inflicted by security forces against the demonstrators supporting women Moursi .
" Our Honorary screamed and called for a man to avenge the death , " they said in the video .
They also promised to " mothers of the protesters were killed and arrested ... because they will feel happy , " he said and hinted would strike again .
The video shows police dragging women protesters , and also featured a pool of blood on the police crackdown on a sit Moursi supporters at al - Rabaa Adawiya Square , Cairo , August 14 .
Hundreds of people have been killed on that day when police stormed the square after pro- Moursi refused to leave .
They demanded reinstating Moursi , who was ousted by the army July 3 .
Since the overthrow of the Moursi , Egypt was rocked by deadly bombings and shootings targeting security forces .
The most deadly attack was claimed by Ansar Beit al - Maqdis based in the Sinai , a jihadist group inspired by al - Qaeda .
Ansar has carried out attacks in the restive Sinai Peninsula and the Nile Delta and Cairo .
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However , Ajnad Misr claims to have carried out the attack in Cairo , including the murder of a police general at Cairo University , earlier this month .