BENGALURU, June 20 -- A Legislative Council election in Karnataka has unsettled the state's opposition alliance, with the BJP and Janata Dal (Secular) confronting evidence of cross voting within their own ranks after the Congress secured a sweeping victory in the contest. The BJP central leadership has expressed strong displeasure over the results and summoned state leaders to Delhi, officials said on Friday.

Party president Nitin Nabin has called Karnataka BJP chief BY Vijayendra and other leaders to a meeting on June 23 after taking serious note of legislators voting against the official line. The party has also set up a three member committee to investigate the matter.

Within the state unit, Vijayendra acknowledged the scale of the s...