Material found inside the weapons cache in Ceuta last week. REUTERS

More information Ceuta investigation yields arms cache and ISIS flag

An arms cache found last week in the Spanish exclave city of Ceuta belonged to the Islamic State (ISIS), authorities have confirmed.

An analysis of the items located by the Civil Guard as part of a drug bust shows that the weapons belonged to an old terrorist cell that is no longer operational, investigators believe.

Anti-terrorist sources said there is “100% certainty” that the find is tied to ISIS

Besides an Islamic State flag, law enforcement officers found a pen drive with “internal instructions” and “generic information about potential targets” in the northern African city, according to a statement by the Spanish Interior Ministry.

The find represents the first jihadist weapons stash to be found on Spanish soil. Until now, arm caches in Spain had traditionally been linked to the Basque terrorist organization ETA, and known popularly by the Basque term of “zulo” – literally, hole.

Counter-terrorist sources said there is “100% certainty” that the find is tied to ISIS.

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The cache contained four short-range weapons, two submachine guns and several knives. There was also a pen drive and a small flag bearing Islamic State symbols.

The find was made as part of an investigation into an organized gang with ties to the drug trade. As such, investigators were initially reluctant to link it to Islamic terrorism.