Michael Leisner, the 65-year-old who became an internet flash-in-the-pan a few weeks ago for burning a box of incredibly flammable Honey Nut Cheerios to protest General Mills's gay breakfast agenda, died of a heart attack last weekend.

Via The Smoking Gun:

Dwight Denyes, the church’s senior pastor, told TSG that Leisner (pictured at right) apparently died of a heart attack Saturday while waiting in his car for two of his children to finish playing tennis.

Leisner’s death brings an abrupt end to a police investigation of his protest outside General Mills’s corporate headquarters in Golden Valley. In an e-mail today, Stacy Carlson, chief of the Golden Valley Police Department, reported that, “It’s being closed exceptionally, due to the suspect’s death over the weekend.”

RIP in hetero-breakfast-cereal-having Heaven, you fiery warrior.

Hat tip yelahneb.