Citing national security risks, President Barack Obama on Friday blocked a Chinese company from owning four wind farm projects in northern Oregon near a Navy base where the U.S. military flies unmanned drones and electronic-warfare planes on training missions.

An environmental analysis says options including using the range for drones, adding a machine gun range, demolition training and mortar pads.

Aerial drones could begin flying test runs over remote areas of Central Oregon in the near future, if a proposal to open a military operations area to the testing gets federal approval.

President Barack Obama on Tuesday pledged the United States would defend South Korea after what the White House branded a provocative, outrageous attack by North Korea on its neighbor. Its options limited, the U.S. sought a diplomatic rather a...