Gunman breaks into Colorado Supreme Court building

They added that the incident seems unrelated to the court’s recent ruling banning former US president Donald Trump from the ballot. Colorado’s justices have received threats ever since they ruled 4-3 last month that a rarely-used constitutional provision barring from office those who “engaged in insurrection” applies to Mr Trump. Authorities, however, said Tuesday’s incident appears unrelated to that case.

Mr Trump is expected to appeal against that ruling to the US Supreme Court later on Tuesday. “The CSP and DPD are treating this incident seriously, but at this time, it is believed that this is not associated with previous threats to the Colorado Supreme Court Justices,” the Colorado State Patrol said in a statement said, using the acronyms for the state patrol and Denver Police Department. The car crash occurred just by the building in central Denver at 1.15am, after which a man identified by police as Brandon Olsen, 44, pointed a handgun at another person, according to the statement from state patrol, which oversees security at the building.

The gunman then shot his way through a window at the Supreme Court building and entered, authorities said. The statement said Olsen held up an unarmed security guard and got a key that let him into the rest of the building. He made his way to the seventh floor, where he fired further shots and then called 911 at 3am.

Olsen voluntarily surrendered to police and there were no injuries to other people, the statement says.

Several hours after the crash a large shattered window could be seen on the ground floor of the building, with glass spilled out on the pavement.

A state patrol trooper guarded it.