Another prime suspect has been arrested in the Class XII chemistry question paper leak case by the Criminal Investigation Department (CID).

Kiran alias Kumaraswamy (28) was arrested on Tuesday from a farmhouse in Tumakuru district, CID officials said, adding, he is the nephew of Shivakumariah, the alleged kingpin nabbed earlier this month.

"After confirming the identity of the person, he has been arrested. He is the prime suspect in the question paper leak case," CID DGP Kishore Chandra told reporters.

"He had obtained the question paper from the Hanagal (Haveri district) sub treasury with the help of an SDA named Santosh," he added.

Police said they are investigating how the nexus relating to the question paper leak worked.

The exam that first took place on March 21 was cancelled after it was revealed that the question paper was leaked.

On March 31, hours before the rescheduled Chemistry exam was to begin, the Department of Pre-University Education was alerted about question paper leak at two locations in the state.

The state government handed over the probe into the matter to CID, which has arrested several persons including the Officer on Special Duty to state minister Sharanprakash Patil.

The government had suspended 40 officers and other staff of the Pre-University Department and also transferred the Director following the leak.

Over 1.74 lakh students wrote the exam across the state finally on April 12 under strict vigil.