DUMONT, N.J. (AP) — Police say a fifth-grader who jumped to his death from a second-story window at his New Jersey school had lost a chess match and was upset because his opponent didn’t say “checkmate.”

The 10-year-old student at Grant Elementary School leaped to his death last month after playing chess at recess.

A Dumont police file released Wednesday says a lunch aide heard the boy tell his opponent: “Do you want me to do something drastic?”

The lunch aide told investigators that after the chess match, she saw the boy write a note, hand it to his opponent and ask him not to open it right away.

The aide told police she confiscated the note and turned around to see the boy jump. The note’s contents weren’t disclosed.