The Queen, seeking the support of her own son's claims to the throne over those of Surendra, invited Mathabar Singh Thapa back after almost six years in exile. Upon his arrival in Kathmandu, an investigation of his uncle's death took place, and a number of his Pande enemies were massacred. As for Ranajang Pande, he had by that time contracted mental illness and would not have posed any threat to Mathabar. Nevertheless, Ranajang was paraded through the streets and made to witness the execution of his family members, after which he was forced to commit suicide by poison. By December 1843, Mathabar Singh was appointed prime minister; but after a year in power, he alienated both the King and the Queen by supporting Surendra's claim over the throne. On 17 May 1845, he was assassinated, on both the King and Queen's orders, by his nephew, Jang Bahadur Kunwar. The death of Mathabar Singh ended the Thapa hegemony and set the stage for Kot massacre and the establishment of Rana Dynasty, a dictatorship of hereditary prime ministers, which was founded on the basic template provided by Bhimsen Thapa. These events provided the long period of stability the country needed but at the cost of political and economic development.