NEW DELHI (AP) — Police have arrested seven people for allegedly stealing classified documents from the Indian government and selling them to energy companies, a top police officer said Friday.

Three men were arrested after they were caught trespassing and stealing documents from India's ministry of petroleum and natural gas, Delhi Police Commissioner Bhim Sain Bassi told reporters.

The men were caught leaving the ministry building Tuesday after authorities acted on a tip that some individuals were stealing and leaking documents from the ministry. Security cameras had been deactivated and duplicate keys were used to enter the offices of some top officials.

They have been charged with trespassing, forgery and theft, police said.

Four other men, including two energy consultants, were arrested later, Bassi said. One of the consultants was a former economic journalist, who had set up an energy consultancy firm.

The men would steal documents and photocopy them and sell them to independent consultants and energy companies, Bassi said.

The documents found in the men's possession were being studied to assess the extent of damage from the leaks, officials said.

"Some confidential documents were leaked to certain independent consultants and energy companies," Bassi said. "We will analyze the documents that have been recovered and see if the Official Secrets Act needs to be invoked," he said.

Police said executives from several oil companies in India were being interrogated and more arrests were likely.

Petroleum Minister Dharmendra Pradhan said the ministry was aware "such activities were going on and were on the alert."

"The investigating agencies will look into the details and find who all are behind this," Pradhan said.

Police produced the men before a judge Friday and the court sent four of them to police custody until Monday. The others were ordered to cooperate with the investigators.

Energy-starved India imports around 75 percent of its oil to power its economic growth. Information on oil imports and pricing would be invaluable for oil firms.