"A US government laboratory says the country held a subcritical nuclear test in the state of Nevada on February 13.
The Department of Energy's Lawrence Livermore National Laboratory made the announcement on Friday.
The test was the first of its kind since December 2017, and the second under the administration of President Donald Trump. It was the 29th in the United States.
The laboratory says the experiment, dubbed "Ediza," used high explosives to implode plutonium and captured "numerous, detailed scientific measurements.""
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