CHISAGO CITY — Authorities say an after-dark collision involving a snowmobile and ice house on Lake Chisago has left three people injured.

The Chisago County Sheriff’s Office said a man who was assembling a portable ice house and his juvenile son were struck by a man driving the snowmobile shortly before 8 p.m. Friday.

Authorities said the juvenile was airlifted to a hospital, where he is listed in critical condition. His father was transported to a hospital with what are believed to be non-life threatening injuries.

The snowmobile driver was brought to a hospital to be treated for a broken arm and other injuries. Authorities said he admitted he was drinking before the crash. He was later arrested.

Names of the people involved have not been released.