Two children were found dead in a home that was filled with natural gas on Tuesday, and their despondent mother was found there with non-life-threatening arm injuries, authorities said.

Police didn't say how the 5-year-old boy and his 7-year-old sister died, but they said they were treating the deaths as suspicious. They said the children likely had been dead inside the house for at least 24 hours.

Police Chief Brent Larrabee said the children's mother, who was hospitalized, had not been questioned by investigators as of Tuesday night and it was too early to say if any charges would be filed, the New Haven Register reported.

Police officers and firefighters responded to a medical emergency call at the house on Tuesday afternoon and found a "despondent" woman and then discovered the children's bodies, police said. The children's father was notified and was "devastated," police said.

The identities of the children and their parents weren't immediately released.

Police said they believe the gas was deliberately turned on but it was unclear if a leak or breakage could have been the cause.

Three police officers exposed to the gas were hospitalized as a precaution but weren't seriously affected, police said.

Local and state police were investigating along with the New Haven state's attorney and the state medical examiner.