Patna, Sep 17 - In a major setback to Bihar Chief Minister Nitish Kumar, the opposition Rashtriya Janata Dal and its ally Lok Janshakti Party have taken a clear lead on nine seats in the by-elections to 18 assembly constituencies in the state, counting for which was underway Thursday.

The RJD and LJP are reported to have won one seat each. The RJD has won the Kalyanpur seat and LJP the Warisnagar seat. However, the official declaration is awaited.

The ruling Janata Dal-United (JD-U) has taken a clear lead on five seats, while its ally Bharatiya Janata Party (BJP) was leading on one seat.

According to early trends, the Congress party is leading on one seat.

The by-elections for 18 seats were held in two phases in the state.