The Iranian military on Tuesday took two small U.S. Navy boats into custody in the Persian Gulf and are currently holding their crews, U.S. officials said.
"Earlier today, we lost contact with two small U.S. naval craft en route from Kuwait to Bahrain," a defense official told BuzzFeed News. "We subsequently have been in communication with Iranian authorities, who have informed us of the safety and well-being of our personnel."
"We have received assurances the sailors will promptly be allowed to continue their journey," the official said.
CNN and the Associated Press reported the sailors could be released as early as Wednesday morning local time.
Gen. Ali Fadavi, Navy chief of Iran's Revolutionary Guard, speaking on state TV said: "Investigation shows that entry of American sailors into Iran's territorial waters was due to mechanical problems in their navigation system and that issue is being resolved."
U.S. government sources told NBC News that 10 American sailors had been detained after one of the vessels suffered a mechanical malfunction and strayed into Iranian waters during a training mission. Officials told the Associated Press the incident happened near Farsi Island, situated in the Persian Gulf.
Secretary of State John Kerry is reportedly working to secure the sailors' release and President Obama is involved, NBC reported. White House communications director Jen Psaki told CNN that though the president was working on resolving the situation, it would not be the focus of this State of the Union address Tuesday night.
Iran's Fars news agency reported the 10 sailors included nine men and one woman. The sailors, according to the AP, were from the Riverine Squadron 1 in San Diego, and they had been deployed to the U.S. Navy's 5th Fleet in Bahrain.
Fars reported the two boats, each equipped with three .50-caliber machine guns, were some two kilometers (1.24 miles) inside Iranian waters according to their own GPS systems.
White House Press Secretary Josh Earnest told CNN the U.S. was monitoring the situation closely.
"We've received assurances both that our sailors are safe, that they're being afforded the proper courtesy that you would expect," he said. "We've also received assurances that they will be allowed to continue their journey promptly."
Earnest said the president's national security team would be in touch with members of congress to update them on the incident.
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