Hollywood, FL – Seven people – including three children – were transported to a hospital after they suffered carbon monoxide poisoning at a home in Hollywood Monday morning, officials said.

The victims were taken to Memorial Regional Hospital around 6 a.m. after complaining of carbon monoxide poisoning symptoms at a home in the 1900 block of Thomas Street, Hollywood Fire Rescue officials said.

Some family pets were also taken out of the building.

Inspectors responded to the scene to try to determine where the carbon monoxide was coming from. Police said they think it was coming from a tankless water heater system.

Fire rescue workers had been at the home on Saturday and Sunday, taking people to the hospital both times, officials said. But it was unknown if those incidents were also related to carbon monoxide poisoning.