(CNN) -- Baltimore police said they've arrested a suspect in the death of a 16-year-old North Carolina girl whose body was found in a Maryland river a year ago.
The body of Phylicia Barnes was recovered in April last year about 40 miles from where she was last seen in Baltimore, where she was visiting family when she vanished in 2010.
People spotted the body in Conowingo Dam on the Susquehanna River and and flagged down police, authorities said at the time.
Police arrested a man identified as Michael Johnson, 28, Wednesday night and charged him with first-degree murder in connection with the killing, said Anthony Guglielmi, a spokesman for Baltimore police.
Johnson was the ex-boyfriend of Barnes' older half-sister, the family has said. Authorities say he was the last person to see Barnes alive.
Her father, Russell Barnes, said news of the arrest came in the form of "a long overdue call," and says he hopes prosecutors can "make sure justice is served."
Bryan Barnes, Phylicia's brother, wore a pendant containing a picture of his dead sister around his neck as he addressed reporters Thursday. He said he knew Johnson growing up as a child and that there was nothing to indicate that he was allegedly capable of committing murder.
But "there's no way to tell that somebody could be a murder," he added.
The teenage girl said she was going out to get something to eat when she left a Baltimore residence where she'd been spending Christmas with her half-sister and other relatives. She was last seen at the Reisterstown Square Apartments in northwest Baltimore.
The FBI joined the search as dozens of detectives and officers worked around the clock to scour the area. Police also questioned about a dozen people believed to have had contact with Barnes in the hours before she disappeared, searching their homes and cars.
They also collected 40 hours of video from surveillance cameras at nearby businesses and apartment buildings.
Authorities then turned to posting billboards along I-95 in hope of gathering information about the girl's fate.
Later, officials said they feared she had been abducted or harmed.
Last April, Barnes' body was one of two found in the Susquehanna River -- one south and the other north of the Conowingo Dam -- state police said.
Authorities said the other body was that of a black male, which was found floating in water about three to four miles away.
CNN's Devon Sayers and Samuel Gardner contributed to this report.