Union Minister Giriraj Singh Tuesday claimed that Bihar Chief Minister Nitish Kumar's discomfort over BJP flagging "sleeper cells" active in the state and opposing imposition of 'Sharia' in some pockets had led to his dumping the party to join the `Mahagathbandhan'.

Singh, who represents Begusarai in the Lok Sabha, was talking to reporters in Siwan district on the sidelines of a party function.

"The busting of Popular Front of India's Phulwari Sharif module (in July) has proved that Bihar has become infested with sleeper cells", he claimed.

Two persons, including a retired Jharkhand Police officer were arrested on July 13 from Phulwari Sharif area of Bihar's capital Patna, while another person was arrested three days later from Lucknow by Uttar Pradesh Anti-Terrorist Squad in connection with the case.

The union minister said while schools uniformly have weekly holidays on Sunday, in Bihar many institutions are closed on Fridays "in a flagrant attempt at enforcing Sharia law," he alleged.

"BJP was raising these issues in the national interest. But this made Nitish Kumar uncomfortable (asahaj)", said Singh, a known detractor of the JD(U) leader.

"His (Kumar's) discomfort may have cost us (BJP) power in the state. But now that we are in the opposition, we will raise the issue of national security and integrity with even greater force", said the BJP leader.

He also accused the RJD-JD(U) combine of having shown a bias in favour of Urdu medium schools.

"Tejashwi Yadav had spoken of filling up vacant posts to meet the promise of 10 lakh jobs. I have learnt that the new cabinet has instead initiated the process of recruiting Urdu teachers. There seems little concern for general schools and also those where the medium of instruction is Sanskrit", the Union Minister alleged.