SPRINGFIELD, MASS. >> A Springfield teenager police say apparently accidentally shot his 15-year-old girlfriend to death has pleaded not guilty to second-degree murder.

Seventeen-year-old Anthony Diaz was held without bail at his arraignment Monday in Hampden Superior Court. His name has been made public because he is charged as an adult.

Authorities think the April 8 shooting death of Daneyshkalis (DAY'-nish-kuh-lees) Davila was accidental.

Police say the girl's 13-year-old brother witnessed the shooting and told investigators that Diaz was spinning the loaded chamber of a revolver when the cylinder snapped shut and the gun went off. The victim, a high school freshman, was struck in the abdomen.

The suspect fled the scene but was arrested at a relative's home.

Diaz's lawyer did not comment.