Five Janata Dal-United (JD-U) Members of Parliament, including a very senior one, Shivanand Tiwari, were expelled for anti-party activities and indiscipline on Thursday.
Tiwari, who was denied a Rajya Sabha seat from Bihar, had called Bihar Chief Minister Nitish Kumar a "dictator", and a man full of arrogance.
The other expelled MPs were Jainarain Nishad, Purnmasi Ram, Sushil Kumar Singh, Mangani Lal Mandal.
"Four Lok Sabha MPs and Shivanand Tiwari have been expelled for anti-party activities, and for hobnobbing with other parties," said party spokesman K.C. Tyagi.