Spain on Monday summoned Israel’s chargé d’affaires and lodged what Foreign Minister Jose Manuel Albares described as a “formal and forceful protest” over Israel’s interception of a Gaza-bound flotilla, calling it “a new violation of international law,” Anadolu reports.

Speaking at a joint press conference with Egyptian Foreign Minister Badr Abdelaty in Madrid, Albares said Israeli forces had intercepted the Global Sumud Flotilla and that Spanish authorities were closely monitoring the situation, El Mundo reported.

“I do not have the exact number of Spaniards, but it would be around 45,” Albares said, adding that between “one and two dozen” Spanish nationals aboard the vessels may currently be detained by Israeli authorities.

Albares said Spain had already established contact with other governments whose citizens were also on board.

The minister called the interception “a new violation of international law,” and that he remains uncertain about how Israeli authorities will proceed with those detained but stressed that the action itself was an “unacceptable act and an illegal detention.”