According to the 38 North monitoring group of Johns Hopkins University, images taken on October 1 show increased activity at the North Korean satellite launch site in Sohae.
This, the group said on Saturday, could indicate that North Korea is preparing for a new test.
However, the group added that, since some of the structures on the launch pad are covered, "it is unclear whether this activity is related to launch preparations or other operations."
As of late, North Korea has increased testing of nuclear weapons and ballistic missiles.