International Desk: Satellite images appear to show movement at North Korea's main nuclear site which could be associated with the reprocessing of radioactive material into bomb fuel.
Washington's Centre for Strategic and International Studies, a think tank in the US, said the satellite imagery of the Yongbyon nuclear site from April 12 showed five specialised railcars near its Uranium Enrichment Facility and Radiochemistry Laboratory.
It said their movement could indicate the transfer of radioactive material.
"In the past, these specialised railcars appear to have been associated with the movement of radioactive material or reprocessing campaigns," the report said.
"The current activity, along with their configurations, does not rule out their possible involvement in such activity, either before or after a reprocessing campaign."
Any new reprocessing activity would underscore the failure of a second summit between US President Donald Trump and North Korean leader Kim Jong-un in Hanoi in late February to make progress toward North Korea's denuclearisation.
The US State Department declined to comment on intelligence matters.
But a source familiar with US government assessments said that while US experts thought the movements could possibly be related to reprocessing, they were doubtful it was significant nuclear activity.
Jenny Town, a North Korea expert at the Stimson Centre think tank, said that if reprocessing was taking place, it would be a significant given US-North Korean talks in the past year and the failure to reach an agreement on the future of Yongbyon in Hanoi.
"Because there wasn't an agreement with North Korea on Yongbyon, it would be interesting timing if they were to have started something so quickly after Hanoi," she said.
Trump has met Kim twice in the past year to try to persuade him to abandon a nuclear weapons program that threatens the United States, but progress so far has been scant.
The Hanoi talks collapsed after Trump proposed a "big deal" in which sanctions on North Korea would be lifted if it handed over all its nuclear weapons and fissile material to the United States.
He rejected partial denuclearisation steps offered by Kim, which included an offer to dismantle Yongbyon.
Although Kim has maintained a freeze in missile and nuclear tests since 2017, US officials say North Korea has continued to produce fissile material that can be processed for use in bombs.
Last week, Kim said the Hanoi breakdown raised the risks of reviving tensions, adding that he was only interested in meeting Trump again if the United States came with the right attitude.
risingbd/Dhaka/April 17, 2019/AI