By Mark Abrams

PHILADELPHIA (CBS) — Philadelphia mayor Michael Nutter today blasted the owners of the vacant Kensington factory building leveled by a five-alarm blaze last week that claimed the lives of two firefighters (see related story), and is vowing full cooperation with the district attorney’s decision to turn the investigation over to a grand jury (another related story).

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The mayor and fire officials were out this afternoon in the 5200 block of Chancellor Street, where four people — two children, their mother and grandfather — died in a pre-dawn blaze on Monday (see related story), just one week after two firefighters were killed in the Kensington blaze.

After promoting the distribution of smoke detectors, the mayor talked about the DA’s decision to take the Kensington fire probe to a grand jury.

Clearly still irritated with the Brooklyn-based owners of the Kensington building and their nearly three dozen other properties in Philadelphia (related story), the mayor blasted the developers for failing to maintain the Kensington site.

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“They could not come and fix their property or put it in a safe condition,” the mayor said.  “But somehow, some way, in less than a week, they found one of the top criminal lawyers in the city of Philadelphia, the former chief of the corruption unit of the US attorney’s office.”

The mayor says he knows the owners received three violation notices and never responded.

Nutter says fire investigators and personnel from the city’s Department of Licenses and Inspections will cooperate with the grand jury and turn over any documents and investigative reports that are subpoenaed.

In the meantime, he says, a citywide assessment of vacant properties like the Kensington factory is under way to identify the owners and assess the safety of those structures.

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