WAKEFIELD, N.H. (WJAR) — Authorities in New Hampshire said that the four people found dead in a home from suspected carbon monoxide poisoning were from Newton, Massachusetts.

The New Hampshire State Fire Marshal identified the deceased as Matthew Goldstein; 52, Lyla Goldstein; 54, Valerie Goldstein; 22, and Violet Goldstein, 19.

"The New Hampshire Office of the Chief Medical Examiner has determined Matthew Goldstein’s cause of death was carbon monoxide poisoning, and the manner is pending," a release said. "The cause and manner of death of Lyla Goldstein, Valerie Goldstein, and Violet Goldstein remains pending."

Matthew Goldstein taught school in Brookline.

The release said investigators were still working to determine the cause of the carbon monoxide leak. They were focusing on the home's gas heating system.

The four were found dead on Christmas. When they failed to show up for a gathering, relatives asked for a wellness check.

Investigators said no working carbon monoxide alarms were found in the home in Wakefield, New Hampshire.

Carbon monoxide is a colorless and odorless gas that can cause sickness and death. Fire prevention experts urge people to install and maintain carbon monoxide detectors in their home.

Carbon monoxide alarms and smoke alarms are two different things, and both should be used.