A U.S. destroyer seized in the Arabian Sea a “cache of weapons and advanced missile components” apparently belonging to Iran, announced the Pentagon on Wednesday.

The vessel carrying a dissembled part for anti-ship cruise missiles, land-attack cruise missiles, air-defense missiles and anti-tank missiles appeared headed to Yemen, a U.S. official told ABC News.

“On November 25th, a U.S. warship conducted a flag verification boarding in the Arabian sea in accordance with international law of what was subsequently determined to be a stateless vessel, and discovered a cache of weapons and advanced missile components,” said Pentagon spokesperson Cmdr. Sean Robertson in a statement. “An initial investigation indicates that these advanced missile components are of Iranian origin. A more thorough investigation is underway.”

The development exemplified a fear from U.S. defense and administration officials of Iranian weapons and forces being moved to potentially attack U.S. forces.

“I would expect that if we look at the past three or four months, it’s possible they will do something that is irresponsible. It’s possible that they’ll lash out at their neighbors,” Gen. Kenneth McKenzie, head of the U.S. Central Command, told an audience in Bahrain recently. “It is not going to be productive for them in the long term to choose to act out in the military domain. That’s the message that we’re trying to convey.”