The Pentagon claimed that Tehran has promised to return two boats and 10 U.S. Navy sailors who were taken into Iranian custody after their boats experienced mechanical problems and drifted into Iranian waters.

Pentagon spokesman Peter Cook told The Associated Press that the small boats were between Kuwait and Bahrain, near Farsi Island, when they experienced mechanical problems and the U.S. lost contact.

A U.S. defense official said the ten sailors consisted of nine men and one woman who were traveling in two riverine patrol boats.

U.S. officials do not know the exact location of the sailors, but Cook said they have been in contact with Iran and they have been assured that the sailors will be “returned promptly.”

“We have been in contact with Iran and have received assurances that the crew and the vessels will be returned promptly,” Cook said.

When reporting on the capture, the semi-official Fars news agency reportedly claimed that “these two boats were seized by Revolutionary Guard naval forces near Farsi Island 2 km inside Iranian territorial waters.”