Scott Air Force Base has tried to deflect concerns by some that a mail room scare forcing the base to temporarily shut down was tied to the 10th anniversary of the Sept.11 attacks.

In our opinion, it is absolutely not, Col. Mike Hornitschek told the St. Louis Post-Dispatch Wednesday. We're treating it as an isolated incident could happen any day at any mailroom.

The base has nearly reopened once again after three people were taken to the hospital and others were put through decontamination over concerns that they might have been exposed to toxic chemicals at the post office, according to news reports.

Bio-environmental specialists and explosive ordnance disposal technicians have tested the official mail center and have found nothing suspicious in the area, according to a news release.

The base, located approximately 45 minutes east of St. Louis, began investigating Wednesday a suspicious package in the official mail center, an earlier release said. This led to the bases temporary closure, which includes an education center, bowling alley and a tourist wing.

Scott AFB emergency responders are well-trained professionals who provide immediate response, Col. Mike Hornitschek said in a statement Wednesday. They are working diligently to render the area safe and investigating the source of the package.

Hornitschek told the Post-Dispatch that authorities were not sure what in the mailroom might have led to illness, although investigators have been able to narrow the focus to one specific bin of mail. Many parts of the base were reopened by later in the day.

At this time, life and business continues as normal, Hornitschek told the paper. There's no threat to the local community to our knowledge.

The Official Mail center is close for Thursday as U.S. Postal Inspectors and the FBI continue to investigate the cause of the reactions.  All other parts of the base have opened on a normal schedule.