By CBS Baltimore Staff

ADELPHI, Md. (WJZ) — At least 11 people were sickened by carbon monoxide during a church service in Prince George’s County over the weekend, officials said.

Crews were called to a property in the 3000 block of Buck Lodge Road on Sunday for a report of people unconscious. When they got to the scene, they found a group of 25 to 30 people inside a building where a church service was happening. Everyone was conscious.

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Credit: Prince George’s County Fire Department

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EMS crews took seven people to hospitals for evaluation and treatment; multiple other people refused treatment or left the scene, the Prince George’s County Fire Department said.

On Monday morning, four more people went to a hospital with dizziness and vomiting, symptoms of carbon monoxide poisoning.

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The fire department said crews found a natural gas leak and multiple gas-powered wall heaters in the building.

CBS Baltimore Staff