Claremont — Ten people, including five emergency responders, were transported to area hospitals late Thursday night after being exposed to carbon monoxide at a home on Belding Street.

The source of the carbon monoxide poisoning was under investigation, and officials were at the scene on Friday, according to Danielle Cole, the district chief for the Office of the State Fire Marshal.

Cole said a gasoline-powered generator — a possible source of carbon monoxide — was found in the single-family home, but authorities had not yet determined whether it was running.

“It’s something we’re looking into at this point,” she said.

A medical call prompted Claremont police and fire departments, as well as Golden Cross Ambulance, to respond at 11:36 p.m. to the home at 26 Belding St., according to the release.

“Upon their arrival, the first responders discovered that the three occupants of the home were exhibiting signs of carbon monoxide poisoning and there were also highly elevated levels of carbon monoxide inside the residence,” officials said in a news release. “All of the occupants of the home, as well as two friends that came by to visit them, were transported to area hospitals for treatment.”

One person was at Dartmouth-Hitchcock Medical Center, and four were taken to Massachusetts General Hospital in Boston, Cole said. She did not have conditions for them mid-afternoon on Friday.

“It’s something we are keeping an eye on,” she said. “We’re going to have to do some interviews with people who were involved in the incident … hopefully when they recover and we can get some good information.”

The three occupants were tenants in the home, she said. The cause was not considered suspicious, she said.

In addition to those five people, a police officer, two firefighters and two EMS providers also were transported for carbon monoxide poisoning. They were expected to recover, the release said.

Claremont Police Chief Mark Chase said the police officer had been discharged from the hospital and that “no long-term effects” from the exposure were expected.

In the news release, State Fire Marshal J. William Degnan reminded New Hampshire residents about the “importance of having working carbon monoxide alarms in your homes” and knowing the signs of carbon monoxide poisoning.

“Carbon monoxide is a colorless, odorless, tasteless gas that is known as the silent killer,” the release said.

According to the release, signs and symptoms of carbon monoxide poisoning may include:

dull headache,

weakness,

dizziness,

nausea or vomiting,

shortness of breath,

confusion,

blurred vision,

or loss of consciousness.

Anyone who experiences any of those symptoms should immediately get out into fresh air and call 911.

John P. Gregg can be reached at jgregg@vnews.com.