U.S. to List Libyan Groups and Militant Tied to Benghazi Attack as Terrorists The State Department is moving to apply the terrorist designation to two Libyan organizations and one militant believed to have played a role in the deadly attack on the American diplomatic mission in Benghazi in September 2012, senior United States officials said on Wednesday. The terrorist designations would be the American government's first formal public accusations of responsibility for the attack, which killed Ambassador J. Christopher Stevens and three other Americans. Senior United States officials, speaking on the condition of anonymity because the State Department has not yet made the designations public, said they would apply to Ahmed Abu Khattala, a Benghazi militant described by witnesses as having played a role in directing the assault, as well as to an allied group, Ansar al-Shariah of Benghazi, whose fighters were seen participating in the attack. In interviews, Mr. Abu Khattala has denied belonging to Ansar al-Shariah, but the terrorist designation was expected to describe him as a leader of the group. Witnesses said he visited its headquarters the night of the attack. The designation is expected to say that members of the group were involved in it. The designation was also expected to apply to Ansar al-Shariah of Derna, Libya, which is described as a separate militant Islamist organization, the officials said. The designation was expected to assert that its fighters were also involved in the attack. They may have been identified by witnesses or security camera footage. Derna is a coastal city known as a center of Islamist militancy, a few hours" drive from Benghazi in eastern Libya. The designations were disclosed privately to Congress last Friday. Elements of the State Department action were reported on Wednesday by The Washington Post, and they were expected to be released publicly by the State Department on Friday. Many people from Derna, including Islamist fighters, are in Benghazi on any given day, and there is no evidence that the fighters from Ansar al-Shariah of Derna who were involved in the attack came to Benghazi for that reason, according to officials familiar with the intelligence reports, the criminal investigation and the terrorist designations. The designation was also expected to apply to Sufian bin Qumu, a former driver for a company controlled by Osama bin Laden and a former inmate at the United States military prison in Guantánamo Bay, Cuba. He is identified as a leader of Ansar al-Shariah in Derna, but officials briefed on the designations and the intelligence reports said that there was no evidence linking him to the attack. By mid-2013, however, Mr. Qumu was known to have contacts and communication with Al Qaeda or its regional affiliates, such as Al Qaeda in the Islamic Maghreb, according to people knowledgeable about the intelligence. In a recent interview with Libyan television, Mr. Qumu called for the imposition of medieval Islamic punishments like severing the hands of thieves or whipping alcohol drinkers - describing such measures as an obvious step that all but drunks or thieves would support. In a radio interview in 2012, he said he hoped that "an Islamic state is established here" like the one he knew in Afghanistan under the Taliban. If he described Guantánamo Bay, he told listeners, "You will not hold back your tears." A nephew of his, known as Abu Nas, was believed to have run a primitive training camp near Derna for Islamist fighters, presumably bound for fighting elsewhere. In May 2013, the nephew was killed while driving a car loaded with explosives that accidentally detonated in Benghazi, according to officials briefed on United States intelligence. In addition to the Libyan militants, the State Department is also moving to apply the terrorist designation to a Tunisian militant leader, Seifallah ben Hassine, as well as a separate Tunisian organization also known as Ansar al-Shariah. That name is relatively generic and means Supporters of Islamic Law. The designations have legal consequences, allowing the United States to freeze assets belonging to designated individuals or groups, or to block Americans from doing business with them. Federal investigators have filed sealed criminal complaints against about a dozen suspects in the Benghazi attack, but the Libyan authorities have said they are unable to arrest or prosecute the suspects because of the government's lack of a strong military or police force. The United States military has drawn up its own plans to apprehend Mr. Abu Khattala in a commando raid, but the Obama administration has so far held back from carrying them out, in part for fear of toppling Libya's fragile transitional government.