William Spengler, 62, (shown here) sprayed bullets at firefighters who responded to a blaze at his home, killing two and injuring two others.
He then killed himself as seven houses burned on a sliver of land along Lake Ontario. Several guns were recovered, including a .223-caliber semiautomatic rifle.
"He was equipped to go to war, kill innocent people," a police official said. He called the attack a "clear ambush on first responders."