Security has been tightened as officials completed preparations for Thursday's assembly polls in Arunachal Pradesh where three Congress candidates have already been elected unopposed in the 60-member house.

The Chief Electoral Officer Manoj Kumar Parida told reporters that two additional companies of central para-military forces had been rushed to the state.

With this a total of 42 companies of para-military forces had been given to the state by the central government for conducting the election in 1684 polling stations spread over 57 assembly constituencies.