According to US cable network CNN, an unnamed "general" who allegedly works in the Egyptian intelligence apparatus, claimed on Thursday that Sunday's Sinai border attack might have been the work of the "Al-Galgala Army," which, he alleged, consists of former Hamas members who broke away from the Gaza-based group due to their "extreme ideologies."
The general, who spoke anonymously, asserted that the organisation boasts "hundreds" of militants in the region. Its leader, Abdul-Latif Moussa, was killed by Hamas in 2009.
The general cited by CNN also claimed the attackers had entered Egypt's Sinai Peninsula through tunnels from the besieged Gaza Strip. He added that the attack had required the help of Bedouin tribesmen, who, he alleged, had been recruited through financial incentives.
The general went on to say Israel had provided Egypt with the names of "nine terrorists" involved in the attack, stating they were part of a group dubbed "Tawheed wal Jihad," based in Gaza and parts of the Sinai Peninsula.
CNN's unnamed source also said the Egyptian military had sent reinforcements to Sinai on Thursday based on information provided by Israel.
So-called "jihadists" were accused last year of launching an attack on a police station in the city of Al-Arish in northern Sinai in which five Egyptian security personnel were killed.
Some "Salafist jihadists" were also jailed on charges of participating in attacks on Sinai tourist destinations in 2004 and 2005 that killed some 125 people at the Red Sea beach resorts of Sharm Al-Sheikh, Dahab and Taba. No evidence of their involvement in the attacks, however, was ever produced.
On Sunday evening, an attack by unknown assailants near Egypt's border with the Gaza Strip left 16 border guards dead and several others injured. Islamist groups, including Egypt's Muslim Brotherhood and Gaza Strip-based Hamas, unanimously condemned the attack.