Why Balarama killed Romaharshana?
Romaharshana was sitting in brahma-sthana of the yajna. He was not supposed to get up. When Balarama came everybody else got up except Romaharashana. Balarama thought it was out of disrespect, got offended, and killed Romaharshana.
Glory of Venkatesha
Story of Sri Yantra