National security adviser John Bolton on Sunday refused to comment on commercial satellite images appearing to show the reconstruction of a long-range rocket launch site in North Korea.

“I’d rather not get into the specifics on that,” he told ABC News’ Martha Raddatz on “This Week.”

“The United States government ... expends a lot of resources and effort so we don’t have to rely on commercial satellite imagery,” he said.

Beyond Parallel, an initiative of the Washington-based Center for Strategic & International Studies, on Tuesday published the photos in a report saying the Sohae facility, which had been inactive since August, was rapidly being rebuilt. It published additional evidence Saturday.

Bolton’s response to the images remained vague.

“We’ve seen a lot in North Korea,” he said. “We watch it constantly. There’s a lot of activity all the time in North Korea, but I’m not going to speculate on what that particular commercial satellite picture shows.”