In a statement, the CBI said that Colonel A K Singh, physical training officer and presiding officer of the board appointed by NDA for recruitment, was arrested.
"Singh was arrested after a special CBI court in Pune rejected his anticipatory bail plea. Searches are being carried out at Singh's residence in Purnia and Saharsa district," the CBI said.
Singh is the second serving colonel to be arrested. Earlier anti-corruption wing of CBI had arrested seven others in the scam which included Colonel Kulbir Singh.
Col Kulbir Singh was a staff officer to a NDA commandant, Suhas Shankar Waghmare, Establishment Officer of NDA.
During searches last week in this case, the CBI claimed to have recovered Rs 1.76 crore cash and a list of candidates' names and interview letters and also a list of those who had paid bribe.
The others arrested were NDA employee Ramesh Gaikwad, Bal Kishen Kanojia - who runs a food stall in Pune, his employee Vishnu Sharma and two alleged touts Manoj Sheetak Kar and Dattatre Sheetal Kar.
Meanwhile, a special CBI court in Pune extended the CBI custody of Kulbir Sinh, Kanojia, Sharma and Ramesh Gaikwad till July 5. The two touts Manoj and Dattatre were, however, released on bail.