Authorities identified the shooter as 36-year-old
Mohamed Bailor Jalloh (September 1989 – March 12, 2026), a naturalized
US citizen, who was born in
Sierra Leone, and had been a resident of
Sterling, Virginia. Jalloh previously served as a member of the
Virginia Army National Guard from 2009 until early 2016. He previously pled guilty on October 27, 2016, for attempting to provide material to support the
Islamic State before his arrest on July 3, 2016, and was sentenced to 11 years in
federal prison and five years of supervised release on February 10, 2017. He was registered as inmate #90187-083 based on a document from the
United States District Court for the Eastern District of Virginia, and was incarcerated at
Federal Correctional Institution, Allenwood Low, near
Allenwood, Pennsylvania. He was released early from both Allenwood and federal custody on December 23, 2024, after completing a drug treatment program. Court documents confirmed that Jalloh traveled back to Sierra Leone on June 11, 2015, and returned to the United States on January 16, 2016. During his stay at Sierra Leone, Jalloh became radicalized while briefly living in
Nigeria in August 2015, after meeting with
Islamic State (IS) members and viewing extremist propaganda, including lectures from
Al-Qaeda-linked cleric
Anwar al-Awlaki. On the day before his arrest, Jalloh test-fired and purchased a
Stag Arms 5.56×45mm NATO rifle from the Blue Ridge Arsenal gun store and firing range in
Chantilly, Virginia, after attempting to purchase a
Bushmaster XM-15 rifle at the same store, and failing to purchase another firearm one month earlier in
North Carolina. Jalloh had previously praised
Muhammad Youssef Abdulazeez, who committed the
2015 Chattanooga shootings, in which five people were killed at two military installations. Jalloh told an FBI confidential informant, pretending to be an Islamic State member, that he had considered carrying out a shooting in the United States sometime in summer 2016, during
Ramadan, making references to the
2009 Fort Hood shooting and stating that he believed that such attacks were "100 percent the right thing". ==Aftermath==