PA Gov Josh Shapiro Residence Blaze Seen in New Video, Arsonist Sentenced

9:23 AM PT -- In a press conference Tuesday, Governor Shapiro admitted to battling feelings of guilt following the attack, saying, "The hardest part has been trying to explain it to our children and to our nieces and nephews. I've carried with me this enormous sense of guilt -- guilt that doing this job that I love so much has put our children's lives at risk." He went on to urge that as political violence rises in this country, it's important that none of us grows numb to it. "We need real accountability for acts of political violence, and today is real accountability."

The man who set the Pennsylvania Governor's Mansion ablaze in April pleaded guilty today to arson and other charges ... and new video released shows the crime -- and inferno -- in progress.

Watch the video ... you can see Cody Balmer break a window of Pennsylvania Governor Josh Shapiro's home from the outside, light a Molotov cocktail, and toss it in, starting a blaze.

Balmer, a mechanic, enters the residence through another broken window ... you can see him roaming around inside the home trying to enter various rooms by kicking the doors in. When that fails, he just starts throwing down more explosives in what appears to be the dining room ... before casually exiting through a front door and strolling away across the lawn.

Shapiro and his family were sleeping inside the house at the time.

After entering his guilty plea -- to attempted murder, aggravated arson, arson, burglary, and other charges -- Balmer was sentenced to 25 to 50 years in prison. The plea follows his April arrest when his former girlfriend allegedly told police he admitted to setting fire to the governor's house and asked her to tell the authorities.

Court docs say Balmer surrendered at Pennsylvania State Police headquarters within hours of committing the crime, and gave a blow-by-blow account of the incident, telling officers he was "harboring hatred towards Governor Shapiro."

Balmer said he siphoned gasoline from a lawn mower at his own home and poured it into empty Heineken bottles he collected on his property. He said he took a one-hour stroll to the governor's home while carrying the homemade bombs.

Balmer said he knew his actions would have "negative consequences" and that Shapiro and his family could have been injured while he was lurking inside the home.