9/11 hijacker Khalid Almihdhar is in Yemen when the USS Cole is attacked in Aden harbor there (see October 12, 2000), and is reported to have had a role in the bombing. Almihdhar leaves shortly after the attack, together with al-Qaeda operative Khallad bin Attash. [McDermott, 2005, pp. 209] Bin Attash is quickly identified as one of the masterminds of the operation (see Late October-Late November 2000). Almihdhar will subsequently be accused of participating in the operation by the prime ministers of Yemen and Britain (see Early October 2001 and October 4, 2001). The Yemeni militant group Islamic Army of Aden takes credit for the bombing, and a friend of Almihdhar in San Diego will later say that Almihdhar told him he was a member of that group (see Early 2000). The Cole attack was a repeat of a failed attempt to bomb the USS The Sullivans (see January 3, 2000), of which Almihdhar had foreknowledge (see Late 1999). Almihdhar, who trained with the Cole bombers (see Late 1999) and attended an apparent planning session for the operation (see January 5-8, 2000), may also be involved in a later ship-bombing operation in Singapore (see June 2001). Ramzi bin al-Shibh, a close associate of the hijackers, also leaves Yemen around this time and is also suspected of involvement in the bombing (see October 10-21, 2000).