CAIRO, Jun 13 (Aswat Masriya) - Egypt's Court of Cassation cancelled on Saturday the death sentences served to seven militants last year for killing security conscripts in Sinai, ordering their retrial.

The Cairo Criminal Court had sentenced last December jihadist Adel Habara and six others to death for killing 25 soldiers in Rafah in August 2013.

Militants ambushed a bus in Sinai and shot dead 25 Central Security conscripts after they forced them to leave their transportation on August 19, 2013. The attack, dubbed by the media as the "second Rafah massacre", closely followed the deadly dispersal of two sit-ins set up in support of ousted Islamist President Mohamed Mursi.

Three more defendants were sentenced to life in prison in December. The court sentenced 22 others to 15 years in prison and acquitted three defendants.

All the conviction sentences were nevertheless overturned by the Court of Cassation on Saturday.

The defence team argued that the reasoning of the criminal court's sentence was "corrupt" and lacked causation, adding that the sentence "was based on the Homeland Security's investigation."

The prosecution had accused the defendants of "adopting the ideas of the al-Qaeda militant group; declaring rulers as infidels and assassinating military and police leaders." It added that the defendants "misunderstand Islam". 

The defendants were charged with “committing terrorist acts”, the premeditated murder of the 25 conscripts, spying for al-Qaeda group and establishing an illegal group attempting to stall the constitution and state institutions.

Habara has been sentenced to death in absentia before for complicity in two terrorist bombings in Sinai in 2004 and 2006. He was also sentenced to death last month in session, alongside 7 others.

Militants have stepped up attacks targeting security forces in Egypt, particularly in the Sinai Peninsula, since Mursi's military ouster in July 2013, which followed mass protests against his rule.