According to reports out of the region, the U.S. Navy Arleigh Burke-class guided-missile destroyer USS Jason Dunham intercepted a small sailboat in the Gulf of Aden near Yemen on Tuesday. Navy officials stated that personnel from the destroyer asked the small boat’s crew permission to come aboard as a part of a broader US Naval Forces Central Command operation, and were granted permission.

Once they began to look around the small boat, called a dhow, it didn’t take long for them to discover the massive stockpile of small arms, including hundreds of AK-47s. One Navy official claimed the total count of firearms might exceed a thousand once they’ve all been counted and cataloged. Currently, there has been no official word regarding where the weapons came from or even their ultimate destination, though officials claim to have gathered evidence from the boat that will ultimately shed light on this. There is, however, a strong suspicion that the arms being smuggled are tied to Iranian support for Houthi rebels in Yemen, as U.S. Navy vessels have intercepted previous shipments of supplies in the region that were.

The sailboat, or dhow, was unflagged, meaning it carried no official national registry. This is not uncommon for vessels used to smuggle things into and out of the region that includes Yemen and Somalia and sees heavy shipping traffic as good are transported between Asia, Europe, and the Middle East. Previous U.S. Navy seizures have also included large shipments of drugs.

The U.S. has provided direct support to the Saudi Arabian led coalition of Arab nations engaged in the fight against Iran-backed Houthi rebels, though that support has recently come under scrutiny as American sourced weapons have been used in attacks that some experts characterize not as acts of war, but rather as war crimes. Although the same panel of experts attested that the Houthis themselves might also be guilty of violating international law and norms regarding their own actions in the conflict, some have begun to raise questions about America’s responsibility to ensure they support only responsible and formally humane combat efforts.

“The report had several methodological fallacies and misconstrued the facts of the conflict … ignoring the true reasons for the conflict which are the coup of the Iran-backed Houthi militias against the legitimate government in Yemen,” a Saudi statement released by their government-owned news outlet SPA reads.

The Houthi rebels have been known to fire missiles into southern Saudi Arabia, occasionally even aiming for the nation’s capital or assets tied to the Saudi state oil company, Aramco. U.S. Secretary of Defense James Mattis said on Tuesday that American support for the Arab coalition now accused of war crimes was not “unconditional,” but stipulated that America would continue to provide support to the alliance assuming they worked to limit civilian casualties in the ongoing conflict.