Morocco's Interior Ministry says authorities have arrested a Chadian national affiliated with the Islamic State group and unraveled a "dangerous" plot to attack Western diplomatic buildings and tourist sites.

The Chadian was arrested Friday in a safe house in the northern city of Tangiers. The Interior Ministry statement did not identify him.

It said the suspect flew to Morocco from Chad on May 4, landing at the Casablanca airport. It said he had a mandate from IS to organize a terror cell comprised of Moroccans and Algerians to attack Western diplomatic buildings and tourist sites.

It compared the scope of the threat to the simultaneous bombings in Casablanca on May 16, 2003, that killed 33 people.