A Special Investigation Team (SIT) of the Bihar Police on Friday arrested the state's Staff Selection Commission Chairman from Jharkhand in connection with a question paper leak case, an official here said.

Sudhir Kumar, a senior Indian Administrative Service (IAS) officer who heads Bihar's Staff Selection Commission, was arrested along with four of his close relatives from Hazaribag, the official added.

The SIT team was interrogating Kumar and he would be brought to Bihar capital Patna later on Friday, an official at the state police headquarters here said.

Kumar was missing and on the run after the leak of the Bihar Staff Selection Commission (BSSC) question paper surfaced on February 8. Following this, the exam was cancelled.

The examination is conducted for appointment of clerks in the state government, the first phase of which was held on February 5. 

The questions were leaked on WhatsApp, an online chatting platform, as soon as the exam began at 11 a.m. on that Sunday, media reports said.

More than 20 persons, including BSSC Secretary Parmeshwar Ram, have been arrested till date in the case.