The Egyptian interior minister said on Sunday that leaders of the Muslim Brotherhood in Turkey and the group's Palestinian offshoot Hamas were behind the assassination of top prosecutor Hisham Barakat on 29 June, 2015.

Barakat died from injuries sustained in a Cairo bomb attack; the only successful assassination attempt against a state official since an upswing in militant violence following the 2013 ouster of Islamist president Mohamed Morsi.

Interior Minister Magdy Abdel-Ghafar said that Turkish-based leaders of the Brotherhood, from which Morsi hails, masterminded the assassination, while Hamas "provided training for militants to execute it and also took part in planning it."

"We intercepted electronic communications in a way that had never been done in the history of the Egyptian security apparatus," Abdel-Ghafar told a news conference.

"There is a major conspiracy targeting the Egyptian state… It began a long while ago and included a number of militant attacks, including the assassination of prosecutor-general Hisham Barakat."

Abdel-Ghafar said that Hamas was not involved in the operation within Egypt, but planned and provided training for militants in Gaza.

Hamas denial 

Hamas expressed dismay at Abdel-Ghafar's accusations, with spokesman Sami Abu Zuhri describing them as "untrue".

He was quoted by the group's website as saying that Abdel-Ghafar’s claims are not in line with "the efforts exerted to develop relations between Hamas and Cairo."

He also called on Egyptian officials "not to involve Palestinian factions in internal domestic disagreements."

Egyptian officials have more than once linked Hamas to terror acts in Egypt, which spiked following the toppling of Morsi in 2013.

Though Islamic State group affiliate Ansar Beit Al-Maqdis claimed responsibility for a large number of militant attacks in Egypt over the past two years, no one has claimed responsibility for Barakat's assassination.

Abdel-Ghafar added that police had identified a number of apartments across the country where militants were manufacturing explosives.

"All of those arrested were referred to the prosecution... they all admitted to being Brotherhood members," Abdel-Ghafar said.

During the conference, a video was played showing testimonies of a group of people admitting to being involved in terror activities.

They said that the assassination was initially planned for 28 June but was called off after the militants’ “tracking unit” informed the others that Barakat's convoy was not taking its usual path.

The suspects said that former health ministry spokesperson and now-fugitive Yehia Moussa told them to “prepare themselves” for the planned assassination of Barakat. 

Some of the men said they had received training from Hamas in Gaza, including in “tracking” and “planned operations.”