The destroyer USS Mason and a number of allied ships from the nearby counter-piracy task force initially responded to the cargo ship Central Park’s distress calls that it was being attacked on Sunday, DOD said. Three Chinese navy vessels were also in the vicinity on a counter-piracy mission, but did not respond to the distress call, Ryder said.

The Pentagon says the five armed assailants captured by U.S. forces after seizing a commercial ship near Yemen over the weekend were likely Somali and not Iranian-backed Houthi rebels.

The United States says the episode is unrelated to regional tensions, though it is still investigating the firing of two missiles at the Navy ship involved in the rescue.

The Liberian-flagged commercial vessel Central Park, which later appeared to be targeted by missiles launched by Yemen's Houthi rebels, put out an SOS call in the Gulf of Aden. The United States and an unnamed ally—reported as Japan—intervened, according to the U.S. Central Command.

An attack on a commercial shipping vessel, sailing under a Liberian flag but linked to an Israel businessman, was likely conducted by Somali pirates, the Pentagon press secretary told reporters Monday.

A U.S. Navy guided-missile destroyer and allied ships belonging to a counter-piracy task force on Sunday responded to a distress call from the crew of the Central Park, which had been boarded by five armed individuals, Pentagon press secretary Brig. Gen. Pat Ryder said on Monday.