Police have arrested five people on charges of stealing official documents from India's petroleum and natural gas ministry and selling them to energy consultants and companies, the Delhi Police said on Thursday.
The police said in a statement they were tipped off that some people were "trespassing" into ministry offices to steal the documents.
"Investigations further revealed that the stolen documents were being sold to some individual of private energy consultancy companies," as well as to those in the petrochemical or energy industry, the statement said.
The statement did not reveal any names, but an official at Reliance Industries, one of India's largest conglomerates, said it had learned one of its officials had been detained in connection with the case.
The official said the company was unaware of any other details and is conducting an internal probe.
"We are determined to cooperate in every possible manner," the Reliance official said.
Reliance Industries is in international arbitration proceedings with the petroleum ministry over the implementation of higher gas prices and the disallowance of cost recoveries.
Last year, the Federation of Indian Chambers of Commerce and Industry (FICCI) said business espionage was a major threat to Indian firms.
The arrests come months after Prime Minister Narendra Modi's administration installed closed circuit TV cameras to prevent people sneaking out of the ministry with documents of interest to big corporations competing for lucrative oil blocks.
(Reporting by Rajesh Kumar Singh; Additional reporting by Aman Shah in Mumbai; Editing by Tom Heneghan)