A group of private people based in north Delhi and nearby areas was running the racket.
Five aspirants were detained Sunday after they were caught red-handed while talking on phone during the examination at the Sarvodaya Bal Vidyalaya at Deen Dayal Upadhyay Marg near the Income Tax Office in Delhi.
Gang kingpins Mukesh and Rajnish, both residents of village Khera Khurd in north Delhi, were detained with their associates after the detained aspirants named them.
"With the help of an unknown government employee, the gang members managed to leak the examination paper," said a CBI official.
The accused got the paper solved with the assistance of experts, said the official.
According to the official, the gang members communicated the answer keys to aspiring candidates in the examination hall through their mobile phones and other devices in exchange of money.
"The aspiring candidates carried mobile sets and the other devices into the examination hall by concealing those in their clothes," said the official.
Further investigation is on to unearth the entire racket, the official added.
