Gregory Groom, of Rehoboth, confessed to police that he stabbed Kylee Monteiro multiple times with a kitchen knife, according to prosecutors.

The 22-year-old boyfriend of a pregnant teenager who went missing admitted to police that he had gotten physical with her during an argument.

Gregory Groom, 22, appeared before a judge in Taunton District Court to answer to charges of murder, aggravated assault and battery on a pregnant person, domestic assault and battery, and intimidation of a witness for acts committed against 18-year-old Kylee Monteiro, according to Bristol District Attorney Thomas Quinn III.

The boyfriend of a slain pregnant woman whose remains were found in Rehoboth, Massachusetts, appeared in court on Wednesday and was charged with murder.

The day before prosecutors say her boyfriend stabbed her three times, 18-year-old Kylee Monteiro sent an ominous warning to her sister: "If I die it was Greg."

The ex-boyfriend of a missing 18-year-old who was 11 weeks pregnant has been arrested after her remains were discovered, officials said.

Gregory Groom initially stuck to his story for several days, but during a follow-up interview at Rehoboth Police Station, he admitted to the murder and then told police where he put the body of 18-year-old Kylee Monteiro.