NEW YORK (CBSNewYork/AP) — FDNY Commissioner Daniel Nigro said the department will never forget the ultimate sacrifice made by 12 firefighters half a century ago.

A wreath-laying ceremony was held Monday at the site of the fire on East 23rd Street in Manhattan — the deadliest day in the department’s history until 9/11.

Nigro paid tribute to “the heroes of that awful day and the families they left behind.”

The FDNY Foundation is launching the 23rd Street Fire Legacy Fund in their honor.

The fire on Oct. 17, 1966 began in an art store cellar. Firefighters were trying to reach it through the smoke-filled drugstore next door when the floor caved in. A high-rise apartment building now occupies the site.

Nigro said the lessons of the fire are taught to probationary firefighters.

“Twenty-third Street has been the subject of countless drills, each one passing along vital information that will one day save the life of a New Yorker trapped by fire,” Nigro said.

The department lost 343 members on Sept. 11, 2001.

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