NEW YORK (AP) — Prosecutors are telling jurors that although there were regulatory shortcomings, three construction company supervisors' actions are to blame for two firefighters' deaths at a condemned ground zero building.Prosecutors began their summation Wednesday in the manslaughter trial stemming from the August 2007 fire at the former Deutsche (DOY-cha) Bank building in New York. The building was contaminated with toxic debris in the Sept. 11 attacks. It was being torn down when a fire ripped through nine stories in August 2007.Mitchel Alvo, Salvatore DePaola and Jeffrey Melofchik are charged with manslaughter. Prosecutors say they knew a crucial firefighting water pipe had broken months before, didn't fix it and even took steps to conceal it.The men say they didn't realize the pipe's importance. They say other hazards and regulatory oversights fed the fire.