A jury in Washington, D.C., convicted a second militant involved in the 2012 attack on the U.S. consulate in Benghazi, Libya, that resulted in the death of U.S. Ambassador Christopher Stevens.

The jury convicted Mustafa al-Imam, 47, on conspiracy to provide material support to terrorists and maliciously destroying government property, according to the Washington Post. The jury deadlocked on 15 other charges, including aiding and abetting in murders, and received orders from the judge to renew deliberations.

Ahmed Abu Khattala, a former militia leader in Benghazi, was convicted on similar charges in 2017 and sentenced to 22 years in prison. Khattala was acquitted on 14 charges.

The charges stem from a Sept. 11, 2012, attack on the U.S. consulate in Benghazi. Protests led to a violent attack on the embassy that killed Stevens, CIA security contractors Tyrone Woods and Glen Doherty, and State Department employee Sean Smith.

The suspected attackers involved were captured under battlefield conditions and transported to the U.S. to stand trial in civilian courts. The difficulty of scoring convictions has spread doubt that the U.S. military may attempt to bring any more suspects back to stand trial, however.