A specialized court in Riyadh launched the trial on Tuesday of two Egyptian brothers suspected of planning a suicide attack on a Saudi mosque in cooperation with the Islamic State (IS) group, Saudi newspaper Okaz reported on Wednesday.
According to trial procedures reported by the newspaper, the twins, who were working as blacksmiths in Saudi Arabia, face several charges relating to terrorism in the Gulf nation.
The two 30-year-old brothers, whose identities have not been revealed, were arrested by Saudi authorities in Mecca 17 month ago, according to prosecutors on Tuesday. The brothers were planning to conduct a suicide bombing inside a Saudi mosque, to be later claimed by IS, prosecutors said.
Details of the location of the mosque and the exact timing of the operation were not revealed.
Since mid-2014, the militant group has carried out a series of bombings and shootings in Saudi Arabia that have killed scores of people, mostly members of security forces and Saudi Shias in majority Shia areas.
On several occasions, Saudi Arabia has announced success in foiling major terrorism operations planned by the group in several cities.
One of the two Egyptians on trial has been charged by the country's investigation and prosecution bureau with planning to use an explosive belt to attack the mosque. The attack was to be conducted on behalf of IS following approval from one of the group's leaders in Syria, say prosecutors.
The defendant allegedly recorded a voice message pledging allegiance to the group's leader Abu Bakr Al-Baghdadi, to be used by IS in its media operations after the attack.
The same suspect is charged with joining and adopting the ideologies of the group, as well as closely following the group's propaganda operations through statements released through social media networks.
The second defendant is accused of supporting the group and following it's social media platforms, as well as saving the content provided by the group and re-sharing it on the platforms.
The prosecution added that the first brother saved files relating to jihad on his phone. He also allegedly saved a recorded video left by an IS suicide bomber following a terrorist attack that targeted a Shia mosque in Saudi Arabia's Najran city, killing one and injuring several others.
On Tuesday, the bureau called for the maximum penalty for the two men, saying that it would serve as a deterrent for anyone attempting terrorist operations.
The two defendants pleaded with the court for more time to prepare their defence.
Egypt's foreign ministry was not immediately available for comment on the case.