One Los Alamos National Laboratory employee has been released from the hospital and another is in critical but stable condition after being burned in an accident last weekend at the nuclear weapons research facility.
Lab spokesman Kevin Roark said Wednesday that the investigation into what caused the accident could take weeks or even months. Officials wouldn't release details about the accident.
It happened Sunday while the employees were doing maintenance at an electrical substation that provides power to the lab's Neutron Science Center.
In all, nine workers were sent to the hospital. All but the two were treated and released the same day.
Crews have worked to restore power to some parts of the Neutron Science Center, and Roark says some of the facility's employees have returned to work.
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