Collocations for atrocity - noun

appalling, dreadful, terrible, worst
one of the worst atrocities of the war

alleged | terrorist

be responsible for, carry out, commit, perpetrate
In the war, both sides committed atrocities.

suffer

occur, take place

stories

~ against
atrocities against the civilian population

~ by
reports of atrocities by gunmen

accounts/allegations/reports of atrocities