Original sentence: On May 15, 1974, an elementary school in Ma'alot was attacked by militants belonging to the Democratic Front for the Liberation of Palestine in what became known as the Ma'alot massacre.They killed 21 students on a class trip who were sleeping inside the building
Edited sentence: On May 15, 1974, an elementary school in Ma'alot was attacked by terrorists of the Democratic Front for the Liberation of Palestine in what became known as the Ma'alot massacre.The terrorists killed 21 youngsters on a class trip who were sleeping inside the building