Did Kocharian and Sargsian organize the October 27 assassinations?

During his last rally, Levon Ter-Petrosian said that the Kocharian, Sargsian and Oskanian trio was ready to give the Armenian territory of Meghri and the Southern part of the liberated areas to Azerbaijan in return to Karabakh and the Lachin corridor (very much like the Goble plan proposed in 1989). Karen Demirchian and Vazgen Sargsian disagreed and later paid for it with their lives, Levon Ter-Petrossian alleged.

Obviously, any version of the Goble plan would be the beginning of the end for Armenia. I remember there was a lot of publicity in October 1999 right before the 27-th.