LOS ANGELES - Some 1,500 active-duty US Army paratroopers have been placed on alert for a potential deployment to the state of Minnesota, US media reported on Sunday, citing defense officials.

The soldiers are from the 11th Airborne Division, based at Joint Base Elmendorf-Richardson in Alaska, according to ABC News.

ABC News quoted an official as saying that US President Donald Trump had not made a final decision on whether to deploy two battalions.

"We are taking prudent steps to prepare active-duty Army forces," the official said. "This doesn't mean they will deploy; we are preparing options."

The 11th Airborne troops were recalled to base on Friday, amid the long holiday weekend, to stand by as a so-called quick reaction force, according to an internal notice to the unit's leadership reviewed by ABC News.

Trump on Thursday threatened to invoke the Insurrection Act in Minnesota. The Insurrection Act of 1807 is a federal law that gives the president authority to deploy the US military domestically under certain extreme circumstances. Trump has repeatedly signaled his willingness to invoke the act.

On Jan 7, a US Immigration and Customs Enforcement officer fatally shot Renee Good, a 37-year-old mother, triggering nationwide protests. Demonstrations intensified in Minnesota following a second related shooting within about a week.

Authorities said on Saturday that the Minnesota National Guard has been mobilized as tensions remain high in Minneapolis, the state's largest city.