Four crew members of an unflagged vessel that U.S. officials say was carrying Iranian-made missile components are scheduled to appear Tuesday in a federal courtroom in Virginia, where prosecutors are expected to argue they should be held without bond while they await trial.

The night of Jan. 11, U.S. Central Command Navy forces, including Navy SEALs, along with members of the U.S. Coast Guard Maritime Safety and Security Team, boarded the vessel in the Arabian Sea, off the coast of Somalia. Two Navy SEALs drowned during the operation.

U.S. officials said Navy Special Warfare Operator 1st Class Christopher J. Chambers slipped into the gap created by high waves between the vessel and the SEALs’ combatant craft. As Chambers fell, Navy Special Warfare Operator 2nd Class Nathan Gage Ingram jumped in to try to save him, according to U.S. officials familiar with what happened. Efforts to find and rescue them were unsuccessful.

IRAN ORDERS PROXY GROUPS TO LAY OFF ATTACKS ON US MILITARY IN IRAQ, SYRIA

During a search of the ship, U.S. forces found and seized Iranian-made advanced conventional weaponry, including critical parts for medium-range ballistic missiles and anti-ship cruise missiles, a warhead, and propulsion and guidance components, an FBI agent wrote in an affidavit. The agent said the items found are consistent with weaponry used by Houthi rebel forces in recent attacks on merchant ships and U.S. military ships in the region.

All four men were carrying Pakistani identification cards.

Muhammad Pahlawan is charged with attempting to smuggle advanced missile components, including a warhead he is accused of knowing would be used by the Houthi rebels against commercial and naval vessels in the Red Sea and surrounding waters. He is also charged with providing false information to U.S. Coast Guard officers during the boarding of the vessel.

Pahlawan’s codefendants — Mohammad Mazhar, Ghufran Ullah and Izhar Muhammad — were also charged with providing false information.

Attorneys for the men have declined to comment.

Another 10 crew members are being detained under the federal material witness law. It allows courts to issue warrants for the arrest and detention of a person if their testimony is “material in a criminal proceeding,” and if it “may become impracticable to secure the presence of the person by subpoena.”

The FBI affidavit states that crew members had been in contact multiple times by satellite phone with a member of Iran’s paramilitary Revolutionary Guard.