Houston, TX — Four members of a northwest Houston family were rushed to the hospital with carbon monoxide poisoning Tuesday afternoon.

Cy-Fair Fire Department crews found the victims inside the home in the 17000 block of Cairnlassie.

One of the patients is a 3-year-old child, according to the fire department.

The child and two other family members were in serious condition when they arrived at Memorial Hermann Hospital. An older man was last reported in critical condition.

One of the family members was able to call 911 when they started feeling sick.

Experts warn generators should only be used outdoors.