Valmiki Ramayana Sundara Kanda Sarga 46 Shloka 1

रावणः Ravana, महात्मना the great, वानरेण by the vanara, मन्त्रिसुतान् sons of the ministers, हतान् killed, बुद्द्वा knowing, संवृताकारः who had concealed his agony, उत्तमाम् good, मतिम् thought, चकार formulated.

Coming to know that the seven sons of the ministers were slain by the great vanara, Ravana, who had concealed his feelings of agony thought of a good plan. Five Generals of Ravana done to death by Hanuman in war