Mnuchin has yet to comment on the package.
The LAPD said the Secret Service took over the investigation.
A Christmas card discovered inside made negative references to Mnuchin, President Donald Trump and the $1.5 trillion tax bill that Trump signed into law Friday, police said. It was left in a neighbor's driveway and prompted a response from the LAPD's bomb squad. There were no threats inside of the card. He was inside of his home at the time.More news: Putin thanks Trump for CIA's help in stopping terror attacks
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Mnuchin was not in the area. His street, however, was closed temporarily.
Police eventually determined the package did not contain an explosive device, and the scene was cleared around 9:30 p.m. PT.
"We have $50 million homes and we can't move, we can't get out", Prince Frederick von Anhalt, who was trapped for two hours, said. You have $50 million houses and all of a sudden we can't move? "That's bad. They have to find another way".