More serious charges were filed Thursday against a snowmobiler accused of hitting and fatally injuring an 8-year-old boy last week on a Chisago County lake.

Charges against Eric J. Coleman, 45, who lives in Chisago City roughly a mile from the crash scene on Chisago Lake, were updated to one count of criminal vehicular homicide, one count of criminal vehicular operation and drunken driving.

Before second-grader Alan Geisenkoetter Jr. of Wyoming, Minn., died late Wednesday, Coleman had faced lesser charges.

Alan’s mother, Eleanor, wrote Wednesday night on his site: “Life changed today … Alan’s brain damage was way worse than any of us thought. There was never a day we thought we would have to make a decision like this, the hardest decision we’ve ever made. Little Alan got his angel wings today.”

About 8 p.m. Friday, the boy and his family were preparing to go ice fishing on the north end of Chisago Lake when Coleman’s snowmobile roared through the family’s portable icehouse and clipped their pickup truck. The sports vehicle hit Alan, who had moved to the truck’s tailgate to watch the snowmobile, then dragged him across the ice, critically injuring him.

His mother and younger sister were also in the pickup but were not hurt. His father, who had been setting up the icehouse when it was hit by Coleman’s snowmobile, was also injured, but not severely.

Coleman was injured and also hospitalized. He admitted that he had been drinking and was arrested, the Chisago County Sheriff’s Office said.

Coleman had previously been charged with drunken driving, most recently in November in Anoka County, where he was involved in a crash. His blood alcohol content in that incident was measured at 0.30 percent, nearly four times the legal limit for driving in Minnesota.

That charge prompted the state to revoke Coleman’s license. His vehicle also has an ignition-locking system meant to prevent him from driving after drinking, the criminal complaint read.

Coleman’s other drunken-driving convictions came in 2009 in Ramsey County and more than 20 years ago in Anoka County.