The U.S. Navy has rescued 13 Iranians held hostage by pirates for up to 45 days in the Arabian Sea, the military said Friday The rescue was performed Thursday by forces from the John C. Stennis Carrier Strike Group, part of the 5th Fleet that was warned this week by Iran not to pass back through the Strait of Hormuz. According to a Navy press release, forces flying off the guided-missile destroyer USS Kidd detected a suspected pirate vessel alongside Iranian fishing dhow Al Molai, which had also sent out a distress call saying it was being held by pirates. Al Molai's crew was detained for between 40 and 45 days, enduring harsh conditions and possibly being forced to assist the pirates in other operations against their will, the Navy said. "When we boarded, we gave them food, water, and medical care," Josh Schminky, a Navy Criminal Investigative Service agent aboard the Kidd, said in the statement. Fifteen suspected pirates are currently being detained aboard the USS John C. Stennis. They had been using the Iranian vessel as a "mother ship" for pirating operations in the Persian Gulf, the Navy said. U.S. officials say the Iranian captain expressed his gratitude. The rescue comes amid escalating threats from Iran that it could block the Strait of Hormuz in response to stronger economic sanctions against Tehran over its disputed nuclear enrichment program.