The US Defense Department has released new photos of debris from a Chinese balloon that was shot down off the South Carolina coast on February 4.

The latest photos released on Monday were taken at a military base in Virginia.

They show troops placing what appear to be balloon fragments on the back of a vehicle. The pictured troops were reportedly preparing to transport the materials to another facility for analysis.

Three other aerial objects have been downed since Friday. They were shot down over Alaska, Canada and Lake Huron on the US-Canadian border.

Defense Secretary Lloyd Austin told reporters after arriving in Belgium on Monday that crews have not recovered any debris from the three recent shoot downs.

Austin said, "Right now, our priority is debris recovery so that we can get a better sense of what these objects are."

US authorities plan to work with their Canadian counterparts and speed up the recovery work.