The missing crew members were not identified, and it was not immediately clear which ship they were trying to board or why. US forces regularly partner with other countries as part of the anti-piracy mission operating in the Gulf of Aden. Those missions sometimes include boarding ships to ensure they hold the right credentials or are not carrying illegal goods.
A US official familiar with the incident said it was not related to recent US-led strikes in nearby Yemen. The official said it was unrelated to Iran's seizure of a Marshall Islands-flagged tanker.
The U.S. Central Command, which coordinates military operations in the region, declined to provide more information on the missing service members, Navy sailors and crew members “until the rescue operation is complete.”
Special operations forces in the region have faced tough counter-terrorism missions and other tough operations. In November, five crew members of the elite aviation unit were killed during a refueling accident off the coast of Cyprus.
ABC News first reported on the missing seals.
This is a developing story and will be updated.