Five people were found dead of suspected carbon monoxide poisoning at this Oxon Hill home. (Mark Gail/THE WASHINGTON POST)

The five, all adults, were found in a home in the 700 block of Shelby Drive, according to Marc S. Bashoor, Chief of the Prince George’s County Fire/EMS Department.

Bashoor said the early investigation has shown that the exhaust pipes in the home’s heating system were “rusted and separated” and that carbon monoxide was pumped inside instead of venting out.

“The reality is these people were affected very quickly by large quantities of carbon monoxide,” Bashoor said.“There is no indication of anything other than a tragic loss here, a tragic accident.”

Friends, who stood just outside the yellow caution tape that surrounded the home, said the five were immigrants from El Salvador who attended the same local church. Friends identified them as Oscar Chavez, Sonia Chavez, Nelson Landaverde, Javier Segovia and another woman whose name they did not know. Oscar and Sonia Chavez were married, the friends said, and the others were unrelated friends who lived with the couple.

Siomara Garcia, 39, who attends church with the victims, said Sonia Chavez was about 60, Oscar Chavez was about 55, Landaverde was about 40, Segovia was between 30 and 35, and the other woman was about 35. Fire officials would only confirm they found two men in their 30s, one man in his 40s and two women in their 60s inside the house — though they said they were working to confirm their identities and ages.

Siomara Garcia said all were “nice people” who were “very, very happy in the church.”

Siomara Garcia said Oscar Chavez’s son, who lives nearby in Oxon Hill, found the bodies after his father and Nelson Landaverde’s boss called to report that the two did not arrive at work Tuesday morning. Angel Diaz, 34, who said he works with Landaverde and attends the same church, confirmed that account.

Diaz said he had just seen Landaverde, a friend of his for nearly four years, Monday night at a church band practice. Landaverde, he said, sang, while he played the piano. He said friends were still struggling to understand what happened.

“It’s hard,” Diaz said. “He was real nice. . .like family.”

Officials said firefighters were called to the home about 10:45 a.m. by a family member of one of the dead who had come to the home to check on a relative and found two people unconscious.

Bashoor said firefighters checked the carbon monoxide level at the front door and found it was 140 parts per million. He said a level of 30 ppm would be fatal over time.

Firefighters immediately removed two unconscious residents, then found three more during a search of the home, Bashoor said. All were pronounced dead at the scene, he said.

Bashoor said carbon monoxide level in the house measured as high as 560 ppm.

Yamileth Coreas, who said she was the daughter of a woman who lived in the house, said she had dinner with her mother last night, and nothing seemed amiss in the home when she left. She said she was working to get details about the incident from police.

Coreas said her mom lived in the house with her husband and a roommate and worked in the bakery at Giant.

“My mom is a hard worker, and she came to this country to live a better life,” Coreas said.

This post has been updated. Check back for the latest updates on this story.

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