The CBI has arrested two persons including a key accused in the NEET-UG paper leak case who allegedly stole the paper from a National Testing Agency's trunk in Hazaribagh in Jharkhand, officials said Tuesday.

With the two arrests, the total number of persons arrested in connection with cases pertaining to leakage, impersonation and other irregularities in the medical entrance exam has now reached 14, they said.

The agency has arrested Pankaj Kumar alias Aditya, a 2017-batch civil engineer from the National Institute of Technology Jamshedpur, who allegedly stole the NEET-UG paper from the NTA trunk in Hazaribagh, the officials said.

Kumar, a resident of Bokaro, was arrested from Patna, they said.

The CBI has also arrested one Raju Singh who allegedly helped Kumar in stealing the paper and passing them on to other gang members, they said, adding that Singh was arrested from Hazaribagh.

The agency, which is probing the alleged irregularities in the medical entrance exam, has registered six FIRs. The FIR from Bihar pertains to leakage of paper while the remaining from Gujarat, Rajasthan and Maharashtra are linked to impersonation of candidates and cheating.

The agency's own FIR on a reference from the Union Education Ministry pertains to a "comprehensive investigation" into the alleged irregularities in the examination.

NEET-UG is conducted by the NTA for admissions to MBBS, BDS, AYUSH and other related courses in government and private institutions. This year, the exam was conducted on May 5 at 4,750 centres in 571 cities, including 14 abroad. More than 23 lakh candidates had appeared for the test.