Iran has said that the Israel-linked cargo ship it seized on the weekend had violated international maritime law and was undergoing “necessary investigations,” AFP reports.

Iranian authorities had previously offered little information about why the Islamic Revolutionary Guard Corps seized the ship MSC Aries ship near the Strait of Hormuz.

“The ship was directed into the territorial waters of Iran because it violated international maritime laws,” foreign ministry spokesman Nasser Kanani said. The ship’s crew failed to “adequately respond to questions from Iranian authorities,” he told a briefing.

“It is certain that this ship belongs to the Zionist regime,” Kanani added, referring to Israel.