MADISON, Wis. >> A Wisconsin police chief says he believes a man accused of fatally shooting his wife and blowing up their house will say she asked him to kill her.

Madison police Chief Mike Koval says 50-year-old Lee Anne Pirus may have been dead for weeks or months before being found in the rubble of their house Friday. Her 59-year-old husband, Steven Pirus, is jailed on possible charges of first-degree intentional homicide, arson and recklessly endangering safety.

The Dane County medical examiner’s office says the victim died from “homicidal firearm trauma.”

Authorities allege Steven Pirus manipulated his home’s natural gas system to cause the explosion. Koval says Pirus may try to “show himself as a humanitarian trying to help his wife.” But, Koval describes him as a “cold, calculated killer.”