Plainfield, NJ – Seven people were hospitalized after a multi-family home in Plainfield filled with carbon monoxide on Wednesday, officials said.

Around 4:30 p.m., firefighters responding to a carbon monoxide alarm on the 300 block of East 7th Street found a number of people complaining of headaches, according to city officials.

Readings showed extremely high levels of carbon monoxide throughout the house, which officials said came from a blocked furnace chimney causing the gas to back up into the home.

The house was evacuated, and seven adult residents were taken to local hospitals, officials said. Their injuries were not considered life threatening