BOSTON -- A Dorchester man has been arrested and charged in connection with the May 8 shooting death of Boston teenager Jaewon Martin, 14.

Police said Timothy Hearns, 20, is also being charged with the non-fatal shooting of another 15-year-old boy in Jamaica Plain.

Hearns was charged with murder and armed assault with intent to murder. He was scheduled to be arraigned in Roxbury District Court at 2 p.m.

Martin was an honors student at the James P. Timilty Middle School in Roxbury.

“Mrs. Martin and her whole family are devastated by Jaewon’s murder. This around-the-clock, tenacious investigation is proof of our promise to the Martin family that we will do everything we can to secure justice for Jaewon,” Boston Police Commissioner Edward Davis said.

“The promise of this young life was ended by the utter irrationality of a man with a gun and no regard for who it killed. Like Cedirick Steele, Steven Odom, and too many other victims of gun violence in Boston, Jaewon was shot dead not because of who he was or what he did but because of where he happened to be -- at a city basketball court -- on a Saturday afternoon," Suffolk County District Attorney Dan Conley said.

Martin was shot at 944 Parker St. on May 8. He was taken to Brigham and Women’s Hospital, where he died of a gunshot wound to his chest.

The second victim was taken to Children’s Hospital and was treated for injuries to his chest and arm that were not life-threatening.