Elementary School Disipline

Opinions please:

Two 5th grade boys have an arguement on the play ground with a boy #1 telling another “you are small I will make you cry” the other boy #2 tells him meet me in the bathroom after school and make me cry if you think you can" boy #1 agrees saying ok.

Boy #2 goes to bathroom after school waiting…boy #1 comes in shortly after…hits boy #2 with a water bottle and starts name calling…boy #2 starts swinging and boy #1 runs out crying.

Do you think boy #1 went to the bathroom with intentions to fight? Or just to use the restroom?

Should boy #1, #2 or both be in trouble for this occurence?

Just curious to others opinions of such a situation!