Jordanian security forces have allegedly arrested a man who they say was affiliated with an Iranian-backed group and plotting to carry out an attack in the country, Arab news outlets reported Monday. The suspect, who was detained with nearly 100 pounds of explosives, was planning to attack Saudi targets in Jordan, the Times of Israel reported.

“This is the most serious case in a decade in terms of the quantity of explosives discovered and their quality,” Al-Arabiya quoted a source telling an Arabic-language news site. Jordan has not seen a terrorist attack since 2005, when a coordinated series of bombings, claimed by al Qaeda in Iraq, targeted three hotels and left 60 people killed.

Monday’s suspect, a member of the Iran-backed Bayt al-Maqdis, was due to make his first court appearance on Monday. The Iranian group is not to be confused with the Islamic State affiliated-group with the same name in Egypt, which claimed responsibility of a major assault in the country's Sinai Peninsula last week.

Charges of “possessing explosive material and planning terrorist acts” will be brought against the detained suspect, the Times of Israel reported. Though details and the exact targets of the attack have not yet emerged, tensions between Iran and Saudi Arabia boiled over in recent months, as Iran, considered a strong ally of embattled Syrian president Bashar al-Assad, has been at odds with Sunni states, including Jordan and Saudi Arabia, over their public support for Syrian anti-government rebels.

Saudi and Iran financial and political interests are generally seen to be at odds with one another. Iran has been charged with plotting attacks against Saudi targets overseas in the past. In October 2011, two Iranian men were arrested in New York City over an alleged plot to assassinate the Saudi ambassador.