A missing Maryland teen has been found dead in a Riverdale creek, where authorities say she was beaten with a baseball bat and stabbed with a machete by teens involved with MS-13.

Prince George's County police tell news outlets that the teens were afraid 14-year-old Ariana Funes-Diaz would alert authorities about a crime they committed together in April. Washington, D.C. police have said that crime was a gang-related kidnapping in which a man was snatched from near a Metro station, taken to an abandoned house and robbed. Police say two people were arrested in that crime.

Now 14-year-old Cynthia Hernandez-Nucamendi, 16-year-old Josue Fuentes-Ponce, and 17-year-old Joel Escobar have been arrested and charged as adults with first-degree murder. Police say Fuentes-Ponce and Escobar are MS-13 members, and Hernandez-Nucamendi had been reported missing.

Funes-Diaz's body was found Wednesday, about a month after she went missing. An autopsy determined she died of blunt force trauma. Authorities say they're working to identity a fourth person involved in the slaying, which comes only months after authorities found a 16-year-old member of the gang stabbed more than 100 times by fellow gang members.

Prince George's County police said in March that Jacson Chicas was stabbed to death at a Maryland home and then dumped on the side of a Virginia road and set on fire. At least five people have been arrested in his death, including a 16-year-old boy charged as an adult with murder. Maj. Brian Reilly said then that "these were his gang member friends who turned on him."

Police suggested that something similar happened to Funes-Diaz.

"This is not two gangs that are warring with each other," Reilly said this week. "This is a gang that turned on its associate."