The governor’s office just sent out this press release.

“We learned of the terror plot last night, and since then, we have been in constant communication with the FBI and the Department of Homeland Security. While no locations in Illinois are known to be targets, we continue to monitor the situation closely. For people who do have to travel today, please be aware that all domestic flights have been elevated to an orange level alert. That means you should give yourself plenty of extra time at the airport. And most importantly, if you see any suspicious acitivity, please report it to the local authorities immediately. If we’re vigilant and if we go about our lives as we normally would, we can each do our part to stand up to the terrorists and show them we won’t be bullied.”

UPDATE: From Sen. Barack Obama:

“Today’s report that British authorities foiled an attack on airplanes traveling from London to the United States is a sobering reminder that the world remains a very dangerous place. It also reminds us how important it is to have strong allies in this fight that can help stop these attacks before they reach our shores. The cooperation between British and U.S. officials and the subsequent precautions taken to secure our people are admirable. I hope in the coming days we do more to secure our ports, our chemical plants, and our airports and railways, as the 9/11 commission recommended long ago.”

UPDATE 2: Latest press release from governor’s office:

Governor Rod R. Blagojevich today directed state homeland security officials to take actions to ensure security at commercial airports in Illinois in the wake of arrests in Britain of terrorists suspected of planning attacks on airplanes between the United Kingdom and the United States.

“While there is no known threat in Illinois, we are reaching out to airports throughout the state to offer assistance if additional security measures are needed. We have special response teams on standby so they can quickly move in if necessary,” said Gov. Blagojevich. “As extra caution and tighter security measures continue in our airports, we appreciate the patience and cooperation of those traveling to or from Illinois. And as we go on with our daily lives, all of us need to remember to be alert and on the look out for suspicious activity.”

The Governor’s top homeland security officials were briefed on the terrorist plot during a midnight conference call with the U.S. Department of Homeland Security. The State contacted the City of Chicago early this morning to offer assistance from the Illinois National Guard for security at O’Hare and Midway airports. While Chicago determined that assistance isn’t needed at this time, the state stands ready to provide additional security forces. In addition, the state has activated the Illinois Law Enforcement Alarm System (ILEAS), the state’s law enforcement mutual aid organization, which is contacting the nine other commercial airports in the state to determine if they are considering additional security measures and notify them that the state will reimburse them for extraordinary expenses related to extra security actions during the Orange alert for air travel.

In addition to O’Hare and Midway, other commercial airports in Illinois are located in Rockford, the Quad-Cities, Peoria, Bloomington, Champaign, Decatur, Springfield, Quincy and Williamson County.

“At this time there is no threat to these airports but we want to ensure that they have the ability to tighten security if deemed necessary to thwart potential copycat incidents,” said Col. Jill Morgenthaler, Deputy Chief of Staff for Public Safety. “Anytime you have security intensified at bigger potential targets, there’s also a concern that small targets may
appear soft, and the presence of armed officers could deter a possible threat.”

The state also has placed the Mutual Aid Box Alarm System (MABAS) hazardous materials teams on alert to support Chicago, and offered the Civil Support Team and the State Weapons of Mass Destruction Teams to Chicago.