Kylee Monteiro, an 18-year-old who was 11 weeks pregnant when she went missing out of Massachusetts in August 2025.

Massachusetts prosecutors say a man admitted to killing his pregnant girlfriend and burying her in the woods following an argument the pair had in early August.

Gregory Groom has been charged with murder, assault and battery on a pregnant person, intimidation of a witness and domestic assault and battery, state prosecutors said in Taunton District Court during the 22-year-old's arraignment hearing on Wednesday, Aug. 20. He was arrested in connection with the death of Kylee Monteiro, 18, who was 11 weeks pregnant with his child.

Monteiro was last seen in early August at Groom’s home in Rehoboth, a town about 46 miles from Boston, prosecutors said. After an initial search of his property was unsuccessful, authorities interviewed Groom, and he admitted to killing Monteiro, prosecutors added. Nearly two weeks after she was last seen, authorities found human remains believed to be Monteiro’s on Groom’s property on Tuesday, Aug. 19.

Groom has been arraigned, and Monteiro’s autopsy is still being completed, according to court statements at the Aug. 20 arraignment hearing.

A lawyer representing Groom did not immediately respond to requests for comment when contacted by USA TODAY on Aug. 20.

Mother-to-be: 'If I die, it was Greg'

Before the remains believed to be hers were found, family members had shared information about Monteiro’s disappearance via a missing persons poster on Aug. 15 and said she was pregnant, had asthma and struggled with balance and stamina.

"The family is deeply concerned about her safety, noting she is not able to live independently without support," the poster says.

According to the missing persons poster, Monteiro was staying at Bethesda House, a home for young mothers in Pembroke, Massachusetts.

On Aug. 6, the day before she went missing, she took an Uber to Groom’s house in Rehoboth, about 34 miles southwest of where she was staying, the poster reads. Set to pick up some of her belongings, she spoke to her sister that day and said she and Groom had a physical altercation, per the poster.

Friends and family hadn’t heard from Monteiro, who was typically active on social media, prosecutors in the case said at Groom’s arraignment on Aug. 20.

Groom reported her missing on Aug. 8 and allegedly told police that she came to his house looking for a place to stay, prosecutors said. They got into an argument and she left his home, walking down the driveway, according to prosecutor's statements from his arraignment.

Prosecutors read one of Monteiro's last text messages to family members, which she allegedly sent on Aug. 6.

"He threw me on the ground and pulled my hair and strangled me," the text message says, per the prosecutor. "My phone is at 4% and if I die, it was Greg."

Groom drew map to Monteiro's body, prosecutors say

Groom told police the child Monteiro was carrying was his, prosecutors said during the arraignment.

Authorities searched Groom’s property on Aug. 14 but found nothing, prosecutors said. Investigators continued to look into the case, and on Tuesday, Aug. 19, they interviewed Groom.

Groom told investigators that on Aug. 6, he argued with Monteiro, pushed her, she fell, and hit her head, according to prosecutors. He added that when she tried to get help, he knocked her phone out of her hand.

During their interview with him on Aug. 19, investigators told Groom they’d search his property again and dig if needed. Groom then drew a map showing police where Monteiro's remains could be found, prosecutors said.

Groom told investigators that he and Monteiro got into an argument behind a shed where he often stayed, prosecutors said. He admitted that on Aug. 6, he stabbed her twice in the neck and once in the chest using a kitchen knife, per the prosecutor's arraignment statements.

He then told authorities that he spent hours digging a hole in the woods about 20 yards from where she died on his property, prosecutors said. Investigators found her remains about five feet underground. She had been buried in dirt and covered by brush, according to the prosecutor's arraignment statements.

Groom is being held in jail without bail, and his next scheduled court appearance is Sept. 10.

Loved ones have started a GoFundMe to help with Monteiro's funeral costs. As of Aug. 20, they have raised over $8,000 of their $14,000 goal.

"This is closure and we are so thankful for everyone’s help in getting here," Catherine Monteiro, her sister, wrote on the fundraiser page. "Obviously there will be court proceedings but we are taking this one step at a time."

Saleen Martin is a reporter on USA TODAY's NOW team. She is from Norfolk, Virginia – the 757. Email her at sdmartin@usatoday.com.

This article originally appeared on USA TODAY: Boyfriend admitted to stabbing, burying pregnant girlfriend, prosecutors say

Reporting by Saleen Martin, USA TODAY / USA TODAY

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