OAKLAND (CBS SF) — Oakland Assistant Fire Chief Sean Laffan died Monday night at the age of 42, fire officials said.

About 5 p.m. Monday, Laffan collapsed at the fire department’s offices at 150 Frank H. Ogawa Plaza. Fire department staff started life-saving efforts and Laffan was rushed to Alta Bates Summit Medical Center.

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Laffan’s family was told and was met at the hospital by fire department command staff, executive leadership, and leaders of the firefighters’ union Local 55.

At about 10:15 p.m. Laffan had a prolonged cardiac arrest and doctors were unable to resuscitate him.

Oakland Fire Assistant Chief Sean Laffan

“We are shaken by this immense loss and focused on restoring the emotional health of this department and the Laffan family who are devastated by this tragedy,” Interim Fire Chief Melinda Drayton said.

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“Sean Laffan was a dedicated member of the Oakland Fire Department. He began his career in Oakland Fire twenty years ago, graduating from the Fire Academy on December 23, 2000, and represented our department and the City of Oakland with distinction and enthusiasm for the fire service and our community throughout.

“Right now, we are working together across all ranks to ensure that his service to the residents of Oakland is honored and celebrated, and we’ll continue to take cues from the Laffan family to ensure we are responsive to their needs and wishes during this extremely challenging moment.”

Laffan was just promoted to assistant chief in June. He was born in Santa Clara and lived in Sacramento, Oakland fire spokesman Michael Hunt said.

Laffan is survived by his wife Sabrina, three sons Cooper, Connor and Caeden, who is a probationary firefighter with the city of Oakland, and his parents.

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“Our hearts go out to the entire Laffan family, and all who knew him, worked alongside him and loved him,” Hunt said.