An 18-year-old teenager was arrested Thursday in connection with three separate killings, dating back to August. That summer killing took the life of a 17-year-old teenager that was just driving by when the guns started blasting.

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The first shooting took place on August 10, when James Mayfield went to Saratoga Avenue, NE along with two other men to confront a man they were angry with. Police said it was during that shooting that a stray bullet hit Jamahri Sydnor, a recent graduate of Wilson High School.

Sydnor's closest friends say they are relieved by the arrest, but it doesn't bring their friend back.

"You know he took somebody who everybody loved. Her mom is one of the nicest people you could ever meet and you just took her daughter away like that. I'm just glad he's caught," Shaniya Wilson said.

Sydnor was the captain of the cheer squad at her school and was just days away from starting college at FAMU. She was also the daughter of a Sargent for DC Police.

Her friends, who have all gone off to college, say Sydnor's spirit will always be with them.

"We go see her grave, we go play music, dance and talk to her just to let her know everything that's been going on. All of us still talk to her in our own ways," Melody Hayes said.

Two others, 21-year-old Philip Carlos McDaniel and 18-year-old Robert Moses, had already been arrested for this shooting.

Police said Mayfield also committed two other killings just this week. On Tuesday, police said Mayfield shot and killed a 38-year-old man outside of a home on the 2200 block of Douglas Street NE. Then on Wednesday, police said he shot and killed a 21-year-old man inside of a house on the 1800 block of Bryant Street, NE.

Later in the day on Wednesday, police said that Mayfield attempted a robbery at the 3100 Block of Berry Road, NE. Police responded to the scene and then found Mayfield at the 3100 Block of Banneker Drive, where he was taken into custody.

Beyond the three murder charges, police said Mayfield is also a suspect in three robberies across Northeast.