A mother and her two sons were found dead Saturday in a camper at a motocross event in Kansas, according to law enforcement and multiple reports.

Authorities have not confirmed what caused their deaths, but family friends shared on a GoFundMe page that the woman and two children died as a result of carbon monoxide poisoning. In the post, the woman was identified as Felecia Richey, while family have told multiple local media outlets that the boys' names were Tysin and Bentley.

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The McPherson County Sheriff's Office, which is leading the investigation into their deaths, has not officially named the victims.

Felicia Richey was pregnant at the time of her death, according to the GoFundMe page, which had raised more than $41,000 as of Tuesday morning.

"We are asking for your help with removing the stress from the family on the cost of arranging their three funerals and time away from work to grieve," the post read. "If you can not support financially, please keep this family in your prayers and share with others."

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What do we know about what happened?

The bodies of the three victims were reportedly discovered Saturday in a camper at a race track in Inman, a city located a little more than 50 miles north of Wichita, the McPherson County Sheriff's Office said in a media release.

The sheriff's office said it is investigating the deaths with the help of the Inman Police Department, but released few other details, including the names of the victims or how they died.

Inman Motocross, the organization that was hosting the Kansas Motocross Championship Series, postponed the competition for a day as a result of the deaths.

Today we hug our loved ones extra tight and say I love you an extra time," Inman Motocross said in a Facebook post. "Our heart goes out the family as they work through this time."

The series resumed the next day, with Inman Motocross indicating in a Facebook post that grief counselors were available on site.

What is carbon monoxide poisoning?

Because it is both odorless and colorless, carbon monoxide is commonly referred to as a silent killer. More than 400 American die each year from unintentional carbon monoxide poisoning not linked to fire, while more than 100,000 visit emergency rooms for treatment, according to the Centers for Disease Control and Prevention.

The lethal gas is found in the fumes produced by the burning fuel of vehicles and other engines, as well as gas stoves, lanterns and furnaces, the CDC says. In vehicles, carbon monoxide poisoning is often caused by leaks in the exhaust system.

The poisonous fumes can quickly build up to fatal levels indoors, poisoning people and animals who breathe it in, according to the CDC. Symptoms often appear flu-like in nature and include headaches, dizziness, weakness, upset stomach, chest pain and confusion.

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected].