The U.S. National Security Agency is launching a program called "Perfect Citizen" aimed at detecting cyberattacks on private companies and government agencies running critical infrastructure such as the electricity grid and nuclear power plants.

Perfect Citizen would rely on a set of sensors deployed in computer networks for critical infrastructure that would flag "unusual activity" signaling an impending cyberattack, according to the Wall Street Journal.

Defense contractor Raytheon recently was awarded with a classified contract for the first stage of the surveillance program valued up to $100 million.

Some industry and government officials with knowledge of the program view Perfect Citizen as overreaching by the NSA into domestic affairs, while other view it as a critical program to fight emerging security threats that only the NSA can manage.

"The overall purpose of the [program] is our Government…feel[s] that they need to insure the Public Sector is doing all they can to secure Infrastructure critical to our National Security," said one internal Raytheon email, the text of which was seen by The Wall Street Journal. "Perfect Citizen is Big Brother."

A U.S. military official said the program was long overdue and would not be a violation of privacy.

U.S. intelligence officials have grown increasingly concerned about possible Chinese and Russian surveillance of computer systems that control the electric grid and other U.S. infrastructure.

"Because the program is still in the early stages, much remains to be worked out, such as which computer control systems will be monitored and how the data will be collected. NSA would likely start with the systems that have the most important security implications if attacked, such as electric, nuclear, and air-traffic-control systems," according to the Journal.

NSA chief General Keith Alexander head of the recently created US Cyber Command said in a speech that the role of the agency is to ""deter, detect and defend against emerging threats against our nation in cyberspace."

"All of us in government recognize that we cannot do this without the help of industry, academia and our allies," he said. "Securing cyberspace is a team sport."