The four crew members were taken into custody during a January 11 operation in which elite US special operations personnel boarded a dhow off the coast of Somalia and seized missile components made in Iran, the Justice Department said in a statement.

The weaponry found aboard the boat "is allegedly consistent with the weaponry used by the Huthi rebel forces in recent attacks on merchant ships and US military ships in the Red Sea and Gulf of Aden," it said.

The four men -- Muhammad Pahlawan, Mohammad Mazhar, Ghufran Ullah and Izhar Muhammad -- made an initial appearance on Thursday before a magistrate judge in Richmond, Virginia.

Pahlawan is charged with unlawfully transporting a warhead and making false statements.

The other three are charged with providing false information to US Coast Guard officers regarding the vessel's crew and cargo.

The Justice Department said all four men were carrying Pakistani identification papers.

Pahlawan faces up to 20 years in prison if convicted of unlawfully transporting a warhead and all four face up to five years in prison if convicted of making false statements.

"The Justice Department will use every legal authority to hold accountable those who facilitate the flow of weapons from Iran to Huthi rebel forces, Hamas, and other groups that endanger the security of the United States and our allies," Attorney General Merrick Garland said.

Two Navy SEALs went missing during the January 11 operation and were declared dead after a 10-day search failed to locate them.

The Huthis have been targeting ships in the Red Sea they claim are linked to Israel in attacks they say are in support of Palestinians in Gaza, where Israeli forces are battling Hamas.