Biden was sworn in as the 46th president of the United States on Wednesday on the steps of the U.S. Capitol.
The Open Skies pact is one of three major treaties Washington abandoned under the Trump administration.
Limitations were set in a 2015 nuclear deal.
Since 2001, the Alabama Army National Guard site has played a significant role in preparing soldiers for Afghanistan.
State police asked that anyone who may have witnessed the incident, or had cellphone video of it, to contact them.
DOD spokeswoman Susan Gough would not comment on what the images show.
Advocates and some lawmakers stress that the stars are aligned to pass significant legislation.
"He represented himself and our Army well through his calm, professional response to the situation -- I'm very proud of him."