Washington: Russian state hackers get the headlines, but nations across the globe are pouring money into cyber espionage units, a development, security experts say, that is allowing smaller nations to close the espionage gap without the satellites or tech muscle of big nations.

"It's very inexpensive. It's very efficient," said John Hultquist, a cyber espionage analyst who's studied the growth of hacking among smaller nations for iSight Partners, a division of FireEye, California-based cyber security firm.

The spate of global cyber espionage has unfolded largely under the public radar.

Hultquist said his firm was tracking several new players, which he declined to identify – "I'd get in trouble for naming them" – that had no prior experience in cyber espionage.

"These would be smaller developing countries that would appear to be building out their own capability," Hultquist said. "It's not just the Chinese anymore or the North Koreans. Some of them are quite good."