The body of Satomi Mitarai was found by a teacher after her attacker returned to class in bloody clothes.
The attacker killed Satomi Mitarai.
It said the body was found... that means she was killed. 
( z1 kill :ARG0 ( z2 person :ARG0-of ( z3 attack ) ) :ARG1 ( z4 person :name ( z5 name :op "Satomi" :op "Mitarai" ) ) )