The Pentagon said on Monday that the attempt to hijack the merchant ship MV Central Park on Sunday appeared to have been carried out by five Somali pirates, who are not members of the Houthi group.
Pentagon spokesman Patrick Ryder said: "We are continuing to evaluate, but initial indications are that these five individuals are Somalis."
Ryder added: "It is clear that the incident is linked to piracy."
The US Navy warship USS Mason responded to a distress call from the merchant tanker MV Central Park on Sunday, which was seized by the militants.
The U.S. military said it had captured the attackers, transferred them to the U.S. destroyer ship, and that MV Central Park and its crew were safe.
In another incident, the US military announced a failed attempt to target the ship and destroyer, with two ballistic missiles launched from areas under Houthi control.
"On November 27, two ballistic missiles were fired from Houthi-controlled areas of Yemen towards the general position of the destroyer (USS Mason) and the merchant ship (MV Central)," the army statement said.
But the statement confirmed that the missiles landed in the Gulf of Aden, about 16 kilometers from where the ships were located.
Over recent weeks, the Houthis have carried out attacks on the Israeli city of Eilat and commercial ships, against the backdrop of the escalating Israeli escalation in the Gaza Strip.