According to local media reports citing authorities, the suspect opened fire at responding police officers after they were called shortly after 1 a.m to the Supreme Court building in Denver.
The officers did not fire back and the suspect, who was not identified, was taken into custody some two hours after officers arrived at the scene, according to a local ABC news affiliate, which said no one was hurt during the incident.
The Colorado Supreme Court has been at the center of a legal battle which has garnered national attention after it disqualified former President Donald Trump from the state's Republican primary ballot for his role in the Jan. 6 attack on the U.S. Capitol by his supporters in 2021.
Authorities have said nothing about any possible connection between the break-in and the Trump case.
The Denver Police Department did not immediately respond to requests for comment.
Colorado's Supreme Court ruled that Trump was barred from the primary ballot by a U.S. constitutional provision that prohibits anyone who "engaged in insurrection or rebellion" from holding public office.
Last week, the Colorado Republican Party asked the U.S. Supreme Court to intervene in the case.
