Sitting Congress member Mukut Mithi and Opposition BJP nominee Tapen Siga filed their nominations on June 9 and did not withdraw from the race on the last date of withdrawal yesterday, Assistant Returning Officer K Habung said here today.
Election for the seat would be held following expiry of the term of office of the incumbent MP on May 26.
Counting of votes would take place on the day of polling itself.
Congress had won 42 (one posthumously) of the total 60 seats in the April 9 assembly elections, while opposition BJP had bagged 11 and its ally People's Party of Arunachal had bagged five seats.
The rest two seats were won by independents.