ALBERT LEA — A local man is in critical condition after an explosion early Sunday morning in the basement of his home on Albert Lea Lake.

Freeborn County Sheriff Bob Kindler said Ronald Irvin Rofshus, 48, suffered a severe injury to his left arm and was transported to Mayo Clinic Health System in Albert Lea. From there, he was taken to the Hennepin County Medical Center in Minneapolis.

Kindler said Rofshus was working with explosive chemicals when they ignited at about 12:15 a.m.

Authorities are still investigating. On Monday afternoon, a Bloomington Bomb Squad truck could be seen outside the house, and Sheriff’s office deputies blocked the road.

Rofshus is part owner of Rofshus Precision Machine, an Albert Lea manufacturer of plastic moldings.