De Blasio took the oath of office moments after midnight Wednesday in front of his home in Brooklyn.
The ceremony was captured on video.
"This is the beginning of a road we will travel together," the new mayor said after swearing in.
De Blasio's inauguration ceremony will be held at noon Wednesday where he'll be sworn-in again by former President Bill Clinton on the steps of City Hall using a Bible once owned by President Franklin Delano Roosevelt.
Jon Passantino is a deputy news director for BuzzFeed News and is based in Los Angeles.
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