“This was a group that was plotting certain operations inside Jordan,” Mr Maaytah told pan-Arab news channel al-Hadath.
Video footage on social media showed security forces taking groups of young Asian tourists up the castle’s steep steps to its main entrance as gunshots were heard overhead.
The castle is one of Jordan’s most popular tourist attractions.
Prime Minister Hani al Mulki told parliament “a number of security personnel” had been killed and that security forces were laying siege to the castle. The Canadian government confirmed one of its nationals had been killed.
Police and witnesses said gunmen had earlier gone on a shooting spree aimed at officers patrolling the town before entering the castle, perched on top of a hill. They used one of the castle’s towers to fire at a nearby police station.
Police said the gunmen had arrived from the desert town of Qatraneh nearly 30 km northeast of Karak city, a desert outpost known for smuggling, where many tribal residents are heavily armed and have long resisted state authority.
