Bihar chief minister Nitish Kumar has launched a scathing attack against Maharashtra Navnirman Sena chief Raj Thackeray, likening him to a saitan (evil spirit).

Nitish Kumar reacted with uncharacteristic anger to Thackeray's remarks against north Indians and the Chhath festival.

"Raj Thakeray is like a saitan, who has the habit of making remarks to continue being in the news by hurting people's sentiments and creating unnecessary controversy," a usually soft-spoken Nitish Kumar remarked.

Protests continued in Bihar for the fourth consecutive day on Sunday against Raj Thackeray's comments.

On Friday, two complaint cases were filed against Thackeray in a Patna court. Both cases were filed under sections 153 and 153A of the IPC for 'making provocative statements with intention to cause riot and promoting enmity between classes'.

According to court sources, February 4 and 5 have been fixed to hear the case against Raj Thackeray. If convicted, Thackeray faces up to three years in prison and a fine.

Raj Thackeray had compared the Chhath festival to a natak (stage act), evoking wide spread protests in Bihar. Angry protestors organised rallies against Thackeray, burnt effigies and demanded action against him.

Chhath is a popular festival celebrated in Bihar, where people make offerings to the Sun God for the well being of their families.

Political leaders, cutting across party lines, slammed the comment made by Raj Thackeray. Chief minister Nitish Kumar, Rashtriya Janata Dal chief Lalu Prasad Yadav and Lok Janshakti Party chief Ramvilas Paswan have all criticised Thackeray's comments.