DOVER - As New York, Pennsylvania and Washington, reeled from terrorist attacks Tuesday, Delaware officials put the state on alert and started mobilizing support for the rescue efforts.

As news of the attacks spread, security at state and federal buildings tightened.

Dover Air Force Base went to its highest alert status shortly after the attacks.

All vehicles entering and exiting the base are subject to search and valid military identification is needed to get on the military facility.

Civilian E-3 employees were directed to leave the base and go home by midday. Flights in and out of the base were curtailed, and all training missions canceled.

"The men and women of Dover Air Force Base are shocked and angered at the outrageous and cowardly terrorist acts of (Tuesday) morning," Col. Scott E. Wuesthoff, 436th Airlift Wing commander, said in a prepared statement.

"We share our president's reaction that freedom itself was attacked this morning and freedom will be defended. The men and women of the 436th and 512th airlift wings will stand together in readiness to go wherever and whenever our nation needs us."

Visitors to Legislative Hall and the Frear Federal Building in Dover were questioned and those without specific business in those buildings were asked to leave.

Delaware State Police spokesman, Cpl. Bruce W. Harris, said the agency was placed on alert.

"We were put on White Alert, which is our lowest form of alert," he said.

Cpl. Harris said detective personnel assisted normal patrol units and personnel who are off-duty are kept on a standby status.

By 11 a.m., Gov. Ruth Ann Minner had ordered public schools closed and sent nonessential state employees home.

"Though there has not been a threat to Delaware and there is no reason for panic, I want to take every precaution," Gov. Minner said.

"This is a time when families should be together."

Superior Court President Judge Henry du Pont Ridgely said all courts across the state were closed shortly after noon.

"We've sent the juries home, and we'll sort things out (today),'' he said.

"As of now, everything is on schedule for (today). If there are changes, we will address those changes (today). We will give notice to the media of any cancellations.''

Gov. Minner spent most of the day at the Delaware Emergency Management Agency headquarters near Smyrna, where she participated in phone conferences with state and federal officials - from the FBI and the Secret Service to the National Guard and state police.

She stressed that Delaware was not in a state of emergency and there was no cause for panic, but said the days ahead "call for caution and awareness."

DEMA director Sean Mulhern said his office was monitoring the situation and taking extra security precautions.

"When there is a threat against the U.S., our plan calls for people to be aware of what's happening around their buildings, to be aware of their surroundings," he said.

By mid-afternoon, Gov. Minner said the state had received a call for help from officials in New Jersey.

The state responded with 50 ambulances and put hospitals in Kent and Sussex counties on alert in case they were needed to treat survivors of the terrorist attacks.

DEMA planner Joe Wessels said his office is responsible for keeping communication flowing between all of the state's emergency agencies.

"All information flows through here," he said.

By the end of the day, Gov. Minner issued a statement that all state offices, public schools and charter schools will resume normal operations today.

"While everyone should be cautious and alert as they work and travel, I know of no reason why we should not return to our routines," she said.

Senior writer Tom Eldred contributed to this article.