A satellite imagery company is reporting increased activity at a North Korean launch site, DigitalGlobe released images that suggest that a missile test is likely within the next three weeks.

North Korea’s Sohae Satellite launch station is showing increased truck and personnel activity and other significant movement around the area such as the bringing in of portable fuel oxidizer tanks.

The United States is aware of the increased activity at the site, and State Department Spokesperson Victoria Nuland and that North Korea has been discouraged from conducting any further missile tests. South Korea’s Foreign Ministry says that they are aware of the situation as well and are monitoring. Spokesperson Cho Tai-Young also stated that South Korea is also discussing the issue with other related countries.

“We would just take this moment to again remind the DPRK that in April of this year there was a presidential statement from the U.N. Security Council that demanded that the DPRK not proceed with any further launches using ballistic missile technology,” Nuland said. The U.S. had already warned Japan and South Korea of a possible missile launch earlier this month according to Japanese newspapers.

Johns Hopkins stated that there had been activity at the launch site last month as long-range motor tests were conducted.

The activity is very similar to the activity that took place before the rocket launch in April. That launch, the fourth attempt by North Korea, failed. North Korea said that that launch was to put a satellite into orbit. The U.S. however, said that the launch was a veiled attempt to test a U.N. sanction-banned ballistic missile. North Korea has long sought to develop an inter-continental ballistic missile with the capability of striking the United States.

That attempted launch in April, even though it failed brought to a halt the international efforts to engage the isolated nation. The United States planned a food relief package for the impoverished country, but that project was shelved after North Korea went ahead with its missile plans.

The timing of the current activity and the potential launch could also be aimed at influencing the December elections in South Korea. North Korea has a history of trying to influence the outcome of elections of its southern counter-part through propaganda attacks or border skirmishes.