A Navy investigation into how sailors ended up in Iranian custody has been completed and will recommend disciplinary action, senior military officials told NBC News.
Ten U.S. sailors spent a night in Iranian custody in January after their two boats drifted into Tehran's territorial waters. The sailors were videotaped during their detention and footage of one sailor appeared to show him apologizing to his Iranian captors.
Cmdr. Mike Kafka, a U.S. Navy spokesperson, confirmed that the 5-month investigation is complete and was "being referred to the appropriate commands for adjudication."
Two senior military officials told NBC New the investigation shows that several things went wrong and several sailors made decisions that ultimately led to the embarrassing event.
"It was a calamity of errors," one U.S. military official said.
U.S. officials initially blamed a navigational error for the incident.
The investigation recommends that the Naval Expeditionary Combat Command and U.S. forces Central Command in Bahrain consider several sailors — some assigned on the boats involved and others in their chain of command — for potential disciplinary measures, the senior military officials told NBC News.
The officials would not say how many sailors will face disciplinary action, but one suggested it could be "more than half" of the sailors detained by Iran.
No charges have been filed against any of the sailors but one person has already been relieved of duty because of the incident. Cmdr. Eric Rasch, who was the executive officer at the time of the incident, was removed from his job last month for what the Navy called "loss of confidence" in his ability to lead.
Members of Congress and the media will be briefed on the investigation on June 30 by Adm. John Richardson, Chief of Naval Operations.
The incident raised tensions between the U.S. and Iran because of the images Iran published of the sailors.
It caused political uproar in the U.S., coming on the day of President Barack Obama's final State of the Union address and just months after a nuclear deal with Iran was signed.