By Sara Kugler
The Associated Press

AP Photo/Eric M. Hazard The fire that claimed the lives of two firefighters burns in the former Deutsche Bank office building, Saturday. Slideshow: Deutsche Bank fire

NEW YORK — New York Mayor Michael Bloomberg on Tuesday defended the decision to send dozens of firefighters into a blaze that killed two of them in a vacant tower next to the World Trade Center site.

"You just can't let a fire go out of control," he said. "The alternative of just standing aside and letting a fire go is not something that was ever considered nor should it have been considered."

A key part of the investigation into the Fire Department's choice to send firefighters into the former Deutsche Bank building will focus on the fact that the building's water supply system was not operational. Investigators found a chunk of the standpipe unattached and lying on the floor in the basement, the city said.

Firefighters turned on the water after arriving at the scene, but because of the broken pipe, it just flooded the basement and never came close to reaching the flames.

"Nobody knows if that (the standpipe) was a contributing factor to the two tragic deaths," Bloomberg said. "That's what an investigation is for."

The troubled building had been plagued with citations before the fire, and received another violation for failure to maintain the standpipe system after investigators made the discovery.

The former Deutsche Bank office building has been a toxic mess since it was damaged on the morning of the Sept. 11 terrorist attacks six years ago, and was being dismantled floor by floor. It once stood 41 stories, but demolition crews had whittled it to 26 by Saturday, when the fire erupted.

Bloomberg said in that investigators still did not know how the fire started.