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NAPA, Calif. - Five students were hospitalized at a high school in Napa after they fell ill during class on Thursday, according to the police department.
Students at Vintage High School reported feeling unwell during their first-period choir class, said the Napa Police Department.
Battalion Chief Ty Becerra from the Napa Fire Department said 25 students needed to be assessed after they complained of nausea, headaches, and fatigue.
Teachers and staff removed the students from the room, and they received medical attention from campus nursing staff and emergency responders.
As a precaution, the fire department ordered a shelter-in-place while firefighters assessed the campus.
Pacific Gas & Electric was called to the campus to check for gas leaks or carbon monoxide in the choir room but found none.
Becerra said the school was also inspected for evidence of drugs but found none.
"We didn’t find anything. There were no readings on our monitors, so we’re still at a loss as to what caused this," he said.
The lockdown was eventually lifted later in the day, and students returned to class. Officials said the music room was deemed safe and students were able to use it after the incident.
Police said parents of the sick students were notified. Authorities have not determined the cause of the illness among the students.
Police said in a statement, "As information is available, we will provide you with an update."
In a statement from Holly Dawson, deputy county executive officer for Communications for Napa County, she said, "The health and safety of our residents is our top priority. We are closely monitoring the situation and will collaborate with NVUSD as necessary."