in 1845, Pg Muda Hashim returned from Sarawak to Brunei, accompanied by British naval captain, Sir Edward Belcher. Pg Temenggong Pg Anak Hashim, the son of SOAS II, plotted to kill Pg Muda Hashim. Then in 1846, Pg Muda Hashim and his family were murdered by certain local chiefs. James Brooke was deeply shocked and angered when he learnt of the massacre.
James Brooke viewed the murdered of Pg Muda Hashim as a personal insult and a challenge to the prestige of Britain. He asked Thomas Cochrane, to punish Brunei. Brunei was unable to defend itself as the British better weapons and warships.Sultan accepted the strict terms of the treaty of 1846 imposed on him by James Brooke on behalf of Britain.