Walking from Louisiana State Police headquarters toward the dark-windowed sedan that would take him to prison, a silent Kenneth Gleason wore sandals and a Boy Scout camp T-shirt.

Police arrested the 23-year-old Gleason early Tuesday and charged him with first-degree murder in the shooting deaths of two black men in Baton Rouge. The first fatal shooting happened last Tuesday on Florida Boulevard, killing 59-year-old Bruce Cofield. Two days later and less than five miles away, on Alaska Street, 49-year-old Donald Smart was shot and killed. Cofield was homeless; Smart was a dishwasher at Louie’s Cafe, a popular hangout among Louisiana State University students.

“It appears to be cold, calculated, planned [against] people who were unarmed and defenseless,” East Baton Rouge Parish District Attorney Hillar Moore said at a news conference Tuesday morning.

Authorities also say Gleason fired shots last Monday at the home of a black family in Sandy Ridge, three houses down from his own residence. Two people were inside, as three bullets hit the front door. Nobody was hurt.

“Had it not been for the swift conclusion in this case, I feel confident that this killer would have probably killed again,” said interim Baton Rouge police chief Jonny Dunham. “He could have potentially created a tear in the fabric that holds this community together.”

Gleason’s arrest Tuesday is only the latest in a series of legal run-ins this past week. A security company last week provided investigators with surveillance video showing a white man in a red car removing his license plate. Using that footage, authorities ultimately found Gleason’s vehicle Saturday.

Also over the weekend, police arrested Gleason on unrelated drug charges. He was bailed out of jail late Sunday, despite authorities declaring him a “person of interest” in the murders. He was arrested again Monday by the East Baton Rouge Parish Sheriff’s Office, after allegedly stealing a copy of “The Hitchhiker’s Guide to the Galaxy” from a Baton Rouge bookstore.

Authorities are still searching for a weapon, though they say ballistics tests determined that the same gun was used in all three shootings. Police were able to tie Gleason’s DNA swabs to shell casings at multiple scenes.

“I think they’ll be talking about this across the nation,” Moore said.

Police have not ruled out suggestions by detectives that race played a role, but officials maintain the investigation into a motive is ongoing.

“We’re going to continue talking to Mr. Gleason, to see if we can get additional information into the reason why,” Baton Rouge police spokesman Sgt. L’Jean McKneely said. “We’re not going to speculate at this particular time.”

McKneely would not confirm reports that police recovered a copy of an Adolf Hitler speech inside Gleason’s home.

Gleason remains the only suspect in the three shootings. The district attorney says his office could seek the death penalty in the case. Attorneys for Gleason maintain their client’s innocence.