The Trump administration sent 300 federalized members of the California National Guard to Oregon early Sunday, after being blocked by a federal court from deploying the Oregon National Guard in that state, according to Gov. Gavin Newsom of California. Mr. Newsom denounced the move as a “breathtaking abuse of power” and said California would sue.

The move came less than a day after Judge Karin Immergut of the U.S. District Court in Oregon issued a temporary restraining order preventing Mr. Trump and the Defense Department from mobilizing 200 Oregon troops for a 60-day deployment there. Mr. Trump had said the troops were needed to respond to demonstrations at an Immigration and Customs Enforcement building in Portland, but the judge wrote that she expected a trial court to agree with the state’s contention that the president had exceeded his constitutional authority.

“They are on their way there now,” Mr. Newsom said of the California troops in a statement. “This isn’t about public safety, it’s about power. The commander in chief is using the U.S. military as a political weapon against American citizens. We will take this fight to court, but the public cannot stay silent in the face of such reckless and authoritarian conduct by the president of the United States.”

The president has pushed to deploy National Guard troops in a number of major U.S. cities, most of them heavily Democratic, and has said that military forces were needed to combat crime and support immigration enforcement. On Saturday, Gov. JB Pritzker of Illinois, a Democrat, said that Mr. Trump planned to send 300 Guard troops to Chicago soon. The president has sent Guard troops to Washington D.C. as well.

Earlier this year, Mr. Trump sent nearly 5,000 National Guard troops and U.S. Marines to Los Angeles during protests there over aggressive immigration enforcement. Most of the troops have since been withdrawn.

A federal judge has ruled that those troops were used illegally for domestic law enforcement. But that ruling has been stayed pending an appeal, and 300 troops remained deployed in Southern California. It was those troops that have been sent to Oregon, Mr. Newsom said.

This is a developing story. Check back for updates.