Al-Darbi was charged in 2014 by a military commission, accused of helping plan the October 6, 2002, attack on the French oil tanker "Limburg" near the port of Mukalla, Yemen. He pleaded guilty in February 2014 to the charges in the expectation of receiving a firm sentence and ultimately being released from Guantanamo, rather than continuing to be held in indefinite detention as he had been for the previous 12 years. At age 39, he was the sixth detainee to plead guilty. Observers expected that he would have to serve at least three and a half more years at Guantánamo before being sentenced, to what is expected to be 9 to 15 years, and then he is likely to be transferred to Saudi Arabia to serve the remainder of that term.