His statement comes a day before President-elect Joe Biden is set to be sworn into office and about two weeks after a politically charged mob stormed the U.S. Capitol, prompting Washington, D.C., to implement strict security measures throughout the city to prevent any future threats.
"The Department of Justice is committed, together with our federal, state and local law enforcement partners, to ensuring a safe and peaceful inauguration – one that reflects our nation's enduring highest values," Rosen said in a statement. "As I have repeatedly said over the last two weeks, the Justice Department will have no tolerance for anyone who attempts to mar the day with violence or other criminal conduct. "
He added that anyone who instigates violence or other criminal activity "will be prosecuted."
The FBI has received more than 200,000 tips related to the Jan. 6 Capitol riots, Rosen said. The bureau has charged more than 100 people in connection to the riots and said last week that it expected "well over 300" open cases to be filed by the end of Jan. 15.
"The American people have demonstrated that they will not allow mob violence to go unanswered," Rosen said. "Violence and senseless criminal conduct are not the right way to resolve differences or promote change in our country."
President Trump tapped Rosen, who was previously appointed to serve as deputy attorney general in May 2019, to replace former Attorney General William Barr, who resigned effective Dec. 23.