DUBLIN (CBS SF) — Two school janitors reported missing in Dublin were found in medical distress in a campus library amid a mystery chemical smell, with one dying at the scene and the second taken to a hospital, police reported Wednesday.

Dublin police responded to Fallon Middle School at 7 a.m. Wednesday after the two janitors failed to return home after their shifts Tuesday. Officers arrived to find a vehicle belonging to the missing workers at the rear of the school.

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A search of the campus resulted in the discovery of the workers, a 29-year-old woman and a 32-year-old man, both in the library and suffering from an unknown medical issue.

Officers detected an unknown chemical smell, and both janitors were carried out of the library and into the open air school courtyard, police said.

Medics arrived but the male janitor was pronounced dead at the scene, while the female janitor was taken to a hospital with unknown injuries. The Alameda County Fire Department and the department’s Hazardous Materials Unit were summoned but no hazardous chemicals or material were found in the building or at the school, police said.

Police said it was unknown what caused their medical issues or the death of the male janitor. The two janitors were not immediately identified.

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The incident was still under investigation and no other information was immediately available from Dublin Police.

Dublin Unified School District Interim Superintendent Daniel Moirao issued a statement confirming the two were part of the school’s custodial team but declined to release their names or provide additional details.

“Our deepest sympathies go out to the family and friends of our lost colleague and also to the students, staff and community of Fallon Middle School,” said Moirao. No matter how strong the Fallon Mustang family is, losing a family member at any time is tragic, but during this time of year, it is devastating.”

Moirao said the district was providing counselors to assist students and staff who have been impacted by the news.

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