(CNN) — North Korea appears to be moving ahead with efforts to improve and possibly modernize its long-range rocket capabilities, according to an analysis of new satellite photos.
Engine tests for the North's long-range rocket program appear to have taken place in late March or early April of this year, analysts at 38 North, a blog run by the School of Advanced International Studies at Johns Hopkins University, have concluded.
"They conducted at least one test of an engine for a long-range rocket, and there may have been more," says Joel Wit, a former State Department official who manages the blog and studied the images.
Over the course of several weeks, the images show the appearance of possible fuel tanks, burned vegetation and a seven-car train parked near the rocket assembly building that might have been used to transport equipment and propellants to the test site.
The site of the latest testing also appears to be the same site from where a long-range rocket successfully launched a satellite into orbit in December. A similar test launch from the same site in April 2012 was deemed to be a failure.
While another test of a long-range rocket does not appear to be imminent, the North still faces a wide range of international sanctions for a program many feel might be a cover to develop long-range ballistic missiles capable of reaching vast distances.
Wit says the latest activity could possibly mean the North got enough data and experience from the most previous launches and could afford to focus on other aspects of the program instead of rushing to another test launch. He stressed it is never certain what the current motives of the regime are.
"It's not a full-up test, like what happened in December or April, but it's part of that process and its one that doesn't get a lot of attention from the outside world either," he said.
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