Media say 14 people were working in the containment area of a nuclear power plant in northeast Spain this week when water used to cool a reactor was unexpectedly released.
El Pais newspaper reported Saturday that the workers were in the building, although none are believed to have suffered dangerous contamination.
Operator Anav said in a statement dated Thursday that "the opening of a valve caused the release of 25 cubic meters (883 cubic feet) of water from the primary refrigeration system toward a pool in the containment building" at its Asco 1 plant near Tarragona. It said the industry regulator had been informed.
The reactor was not fully operational at the time. In 2008 radioactive contamination was found on external surfaces of Asco 1.