The shooting injured 16 other people Sunday, a dozen of them by gunfire, authorities said. One arrest was announced hours later. Many of the injured were students, but Johnson was not.
Jaquez Myrick, 25, of Montgomery, was taken into custody while leaving the scene of the campus shooting and had been found with a handgun with a machine gun conversion device, the Alabama Law Enforcement Agency said. Myrick faces a federal charge of possession of a machine gun, the agency said in a statement. It did not accuse him of using the gun in the shooting or provide additional details.
The agency did not say whether Myrick was a student at the historically Black university, where the shooting erupted as the school's 100th homecoming week was winding down.
It was not immediately known if Myrick had an attorney who could speak on his behalf. He was being held in the Montgomery County jail, online booking records show.
Twelve people were wounded by gunfire, and four others sustained injuries not related to the gunshots, the state agency said. Several were being treated at East Alabama Medical Center in Opelika and Baptist South Hospital in Montgomery, the university said in a statement.
Their conditions were not immediately released, but Macon County Coroner Hal Bentley said he understands that at least one of the people injured has been in critical condition.
The FBI joined the investigation and said it was seeking tips from the public, as well as any video witnesses might have. It set up a site online for people to upload video. The Bureau of Alcohol, Tobacco, Firearms and Explosives also was involved in the investigation, a local prosecutor said.
Tuskegee University canceled classes Monday and said grief counselors will be available in the university's chapel to help students.
The shooting left everyone in the university community shaken, said Amare' Hardee, a senior from Tallahassee, Florida, who is president of the student government association.
"This senseless act of violence has touched each of us, whether directly or indirectly," he said at the school's homecoming convocation Sunday morning.
Sunday's shooting comes just over a year after four people were injured in a shooting at a Tuskegee University student housing complex. Two visitors to the campus were shot and two students were hurt while trying to leave the scene of what campus officials described as an "unauthorized party" in September 2023, the Montgomery Advertiser reported.
About 3,000 students are enrolled at the university about 40 miles (64 kilometers) east of Alabama's capital city of Montgomery.
The university was the first historically Black college to be designated a Registered National Landmark in 1966. It was also designated a National Historic Site in 1974, according to the school's website.