The former chief executive officer who was fired from his position at an Illinois tech company after he was busted for participating in the Capitol riot has spoken out, expressing regret and embarrassment about his participation in the mob violence

Bradley Rukstales attended the initial protest in Washington, D.C., on Wednesday, and when the demonstration devolved into a violent riot, he took part in the chaos and invaded the Capitol building along with other Donald Trump supporters attempting to overturn Wednesday’s congressional certification of Joe Biden as the next president. Rukstales was arrested after joining the insurrection.

Rukstales was then fired from his CEO position at the Schaumburg-based tech company Cogensia on the same day he was hit with federal charges for his role in the riot.

“This decision was made because Rukstales’ actions were inconsistent with the core values of Cogensia. Cogensia condemns what occurred at the U.S. Capitol on Wednesday, and we intend to continue to embrace the values of integrity, diversity and transparency in our business operations, and expect all employees to embrace those values as well,” said Joel Schiltz, the acting CEO in Rukstales’ place.

Rukstales spoke to CBS Chicago at his suburban home in Inverness on Thursday about his regret over participating in the Jan. 6 Capitol attack.

“I was in the wrong place at the wrong time and I regret my part in that,” said Rukstales, who admitted to physically entering the Capitol building.

“Everything that happened yesterday I think was absolutely terrible,” Rukstales said. “I’m sorry for my part in it.”

Rukstales was a part of a pro-Trump mob that forced its way past police barricades and entered the Capitol building on Wednesday as members of Congress were in the process of certifying the election results. Five people have died in connection with the deadly riot, including a U.S. Capitol Police officer, a woman shot by law enforcement as she tried to breach the Speaker’s Lobby in the Capitol, and three others who died in “medical emergencies.”

When asked why he entered the building, Rukstales declined to comment further.

He released a written statement later, saying he entered the Capitol building “to see what was taking place inside.”

“It was the single worst personal decision of my life; I have no excuse for my actions and wish that I could take them back,” he wrote.

After Rukstales was charged with unlawful entry in D.C. Superior Court, federal prosecutors charged him with one count of knowingly entering or remaining in any restricted building or grounds without lawful authority; or knowingly, with intent to impede government business or official functions, engaging in disorderly conduct on Capitol grounds; and one count of violent entry and disorderly conduct on Capitol grounds.

The most serious charges carry sentences of up to 10 years.

The U.S. Attorney in Washington said the rioters could face charges as serious as sedition, which carries a sentence of up to 20 years.

By Friday, 13 people faced federal charges, and 40 others had been charges in superior court for their roles in the attack. At least 83 people have been arrested. Those who breached the Capitol building and assaulted police officers are likely to face more serious charges.

The man pictured in Speaker Nancy Pelosi’s office with his feet propped up on her desk, identified as Richard Barnett, 60, of Arkansas, has been arrested on federal charges of entering and remaining on restricted grounds, violent entry and theft of public property.

The FBI has called on the public to submit video and photo evidence to help identify rioters.

“Today’s charges are just the beginning of the FBI’s ongoing efforts to hold those responsible for the criminal acts of violence and destruction that unfolded during the U.S. Capitol building breach on January 6th,” said FBI Director Christopher Wray. “To be clear, what took place that day was not First Amendment-protected activity, but rather an affront on our democracy. The FBI, along with our local, state and federal partners, is committed to ensuring that justice is served.”