The examination papers of Army Recruitment Board were allegedly leaked following which the Thane Police's Crime Branch conducted raids and arrested 18 persons from Maharashtra and Goa.
Nearly 250 students have also been taken into custody in connection with the paper leak. The recruitment exam was slated to be held on Sunday across the country.
Following a tip-off about the offence, the Thane city police, with the help of their local counterparts, conducted raids at various places and arrested 18 persons since Saturday night from Nashik, Pune and Nagpur in Maharashtra, and Goa.
They also took into custody nearly 350 students, from various parts of Maharashtra and Goa, who allegedly benefited out of the exam paper leak, Senior Police Inspector of Thane Crime Branch Unit-I, Niteen Thackeray, said on Sunday.
The students were allegedly given the exam papers by those who run various coaching classes and some army employees to write the answers in lodges and other places, he said.
The students allegedly were to pay Rs 2 lakh each to the accused for the leaked exam papers, police said.
The raids were carried out following a tip-off and police found some students writing the papers at different places in Thane, they said.
Police are trying to find out the source of the leaked papers.
Further probe in the matter was on.