DUBAI, United Arab Emirates -- The U.S. Navy announced Sunday that it seized a boat in the Gulf of Oman carrying fertilizer used to make explosives that was caught last year smuggling weapons to Yemen.
The British royal navy said it confiscated 2,295 pounds of illegal drugs in the same waters.
The interceptions were just the latest in the volatile waters of the Persian Gulf as American and British authorities step up seizures of contraband during the grinding conflict in Yemen and ongoing drug trafficking in the region.
The U.S. Navy's Mideast-based 5th Fleet said its guided-missile destroyer USS Cole and patrol ships halted and searched the sailboat, a stateless fishing dhow, that was sailing this month from Iran on a well-worn maritime arms-smuggling route to war-ravaged Yemen.
U.S. forces found 40 tons of urea fertilizer, known to be a key ingredient in homemade improvised explosive devices, hidden on board.
Authorities said the vessel had been previously seized off the coast of Somalia and found last year to be loaded with thousands of assault rifles and rocket launchers, among other weapons.
U.N. experts say weapons with such technical characteristics likely come from Iran to support the Houthi rebels.
The Navy turned over the vessel, cargo and Yemeni crew to Yemen's coast guard last week.
Officials also revealed Sunday that a British royal navy vessel had seized on Jan. 15 a large quantity of illegal drugs valued at some $26 million from a boat sailing through the Gulf of Oman.
The HMS Montrose confiscated 1,461 pounds of heroin, 191 pounds of methamphetamine and 641 pounds of hashish and marijuana, the joint maritime task force said in a statement.
The task force did not elaborate on where the drugs came from, who manufactured them or their ultimate destination.
But Iran over the past decade has seen an explosion in the use of methamphetamine, which has bled into neighboring countries.