For the first time, the Department of Homeland Security discovered for a malicious computer code that was created to seize the inner workings of power plants and industrial plants. It is called the "Stuxnet" worm.
"Most of the activity that we've seen over the past several months has involved intrusions into enterprise or corporate networks that's the front office area of a control plant of power plant," said Sean McGurk, director of control systems security for Homeland Security.
Investigators discovered that the computer code is capable of opening and closing doors and gates to allow access for potential intruders.
"It is very targeted and very sophisticated, and that's why it's unique. This is the first piece of malicious code of its complexity that we've ever identified," said McGurk.
The Stuxnet worm is considered serious because it can be unleashed on a wide variety of industries.
"It can be used to purify water. It can be used to generate power. It can be used to build equipment and vehicles. It has a wide variety of purposes," McGurk explained.
But the biggest concern may be aging power plants.
"If you can shut a power plant down, you can affect an entire interconnected infrastructure. In other words, the water will stop flowing, the banks won't operate, you can't pump gas," warned McGurk.
Those links between the administrative networks and the control systems provide gateways for hackers to insert malicious codes, viruses or worms into the programs that operate the plants.
Thirteen teams of government cyber experts are investigating this unusual and complex computer threat.
Homeland Security also has a specialized team in place to quickly respond to cyber emergencies at power plants across the country.
AP contributed to this report.