Egypt will try 292 suspected jihadists for allegedlly plotting to assassinate President Abdel Fattah al-Sisi and the Saudi crown prince, and for attacks in the Sinai Peninsula, a prosecution official said on Sunday.

The group, 151 of whom are already in custody, were referred to a military court for alleged membership of the "Sinai Province," the local branch of the so-called "Islamic State" (IS), which is running an insurgency in the Sinai.

All of the 292 were allegedly involved in 17 operations, including two assassination plots against Sisi - one in Cairo and one while he was on a pilgrimage to Saudi Arabia, the official said.

During a one year investigation, 66 suspects reportedly confessed during questioning.

The official said the assassination plotters were dismissed police officers who adhere to jihadist ideology.

The official alleged the suspects had also planned to kill Saudi Crown Prince Mohammed bin Nayef in the Gulf kingdom and five Egyptian judges.

No further details of the plots or how they were foiled were given.

The prosecution also accuses the group of attacking army and police checkpoints and bases in the Sinai, and of attacking a bus full of South Korean tourists in the south Sinai tourist resort of Taba that killed three holidaymakers in February 2014.

Islamic militants have long been battling the Egyptian army in northern Sinai, but violence has escalated after the military overthrew Islamist president Mohamed Morsi in 2013.

The Egyptian IS affiliate has claimed responsibility for many attacks, including claims it bombed a Russian plane over Sinai in October 2015, killing all 224 people on board, most of them Russian tourists.

aw/bw (AFP)