The US Department of Homeland Security (DHS) is asking all Americans, especially businesses and operators of critical infrastructure, to report any suspicious cybersecurity incidents or intrusions, as part of a nationwide action plan code-named Operation Liberty Shield.
"We ask the private sector and general public to report unusual activity, such as intrusions, hacking and probes, to us via the National Infrastructure Protection Center website or the FBI," said Dave Wray, a spokesman for the DHS.
"We are increasing monitoring of the internet, contact with our information sharing and analysis centres [ISAC], internet service providers and the Internet security industry."
Secretary of homeland security Tom Ridge activated Operation Liberty Shield on 18 March, soon after president Bush issued Saddam Hussein an ultimatum to leave Iraq or face military action.
"We will continue to monitor the internet for signs of a potential terrorist attack, cyberterrorism, hacking and state-sponsored information warfare," said Ridge.
The Department of the Treasury has also increased its monitoring of the nation's financial networks and payment systems.