Police used pepper spray and fired tear gas shells in an effort to control protesters.
At least one older man who was bleeding from the back of his head was taken away in an ambulance. A law enforcement officer said he may have been knocked over accidentally by protesters.
"We must take to the streets and protest, blockade, disrupt, intervene, sit in, walk out, rise up, and make more noise and good trouble than the establishment can bear," the group Disrupt J20 said in a manifesto posted on its web site. Disrupt J20 organized protests designed to distrupt the inaguration activities.
The woman who tried to interrupt Trump's oath of office was heard yelling "Not my president," while standing below the VIP platform on the U.S. Capitol's steps. She was quickly escorted away from the area.
A truck covered in "Trump" bumper stickers was denuded of many of them by protesters walking by the vehicle.
Not all of the protesters were violent.
One draped the fountain in DuPont Circle in Washington, long a focal point for the capital's gay, lesbian, bi-sexual and transgender population, with a red banner saying one word: "Resist!"
NBC News reported that more than 10,000 people gathered at DuPont Circle on Friday morning to collect marijuana cigarettes being handed out for free by a pro-pot legalization group. Marijuana use is legal in D.C.
--NBC News contributed to this article.