According to an American military official, the 358 missile in flight is about nine feet long and can run on kerosene or diesel fuel contained in flexible containers that do not require a separate fuel pump. A dozen infrared lenses arranged in a ring around the missile are believed to be able to defeat heat-seeking countermeasures that coalition helicopters typically use. Another United States military official said that the 358 missiles from Iran had been fired against American drones flying in Yemeni airspace, but they had not yet succeeded in hitting any. Three of the 358 missiles were captured in November by the Forrest Sherman, a Navy destroyer, and five more were recovered this month in an operation by the Normandy, a Navy cruiser. Those shipments also included more than 170 antitank guided missiles made in Iran, as well as 13,000 blasting caps, which are critical to making modern roadside bombs.