LAWRENCE – A 16-year-old boy was arrested Saturday in connection with the death of a fellow teenager whose decapitated body was found on a river bank in this northeast Massachusetts city.

Essex County District Attorney Jonathan Blodgett identified the suspect arrested in connection with Lee Manuel Viloria-Paulino’s death as Mathew Borges, a 16-year-old Lawrence resident.

He was taken into custody at 11 a.m. after state police officers assigned to the DA’s office carried out a search warrant in the early hours of Saturday morning.

“He will be arraigned at Lawrence District Court on a count of murder of the first degree and will be charged as an adult,” Blodgett said.

Borges was believed to be a classmate of Viloria-Paulino at Lawrence High, according to Blodgett. But it is unclear if Borges attended the school regularly.

Viloria-Paulino, a sophomore at the high school, was last seen on Nov. 18. A family friend said he left his iPhone and wallet in his room when he went missing. The family and Lawrence police had posted notices on social media seeking information about the teen. But there was little information forthcoming for the two weeks that passed until a woman walking her dog Thursday afternoon along the river found the mutilated body.

The boy’s body had been decapitated, the head found 50 feet away on a portion of the riverbank behind the Lawrence Boys & Girls Club.

“This was a gruesome, vicious crime,” said Linette Perez, a friend of the family’s. “It’s sickening.”

Earlier Saturday, the family of the slain teenager spoke out against the manner in which Lawrence police handled the missing person investigation.

“We disagree with the investigation of the police at the beginning,” said Viloria-Paulino’s grandfather, Gustavo Paulino, outside the family home.

“Police treated this as a runaway case, even though from day one we told them it was not,” said Ivelisse Cornielle, the grandmother of Viloria-Paulino.

She said the local police only started paying attention when state police got involved.

The family stressed that they don’t feel safe in Lawrence anymore.

“If Lee wasn’t safe, nobody is safe,” said Paulino. “It is our family today but it could be any other.”

Perez said though she never knew Viloria-Paulino personally, his family described him as a normal teenager trying to get by in school and social situations.

“Just the other day he asked permission from his grandmother to go to a party, she said yes and dropped him off, and he called her back 30 minutes later saying it wasn’t his scene and he wanted to come home,” Perez said Friday night outside the family home.

Fellow students, friends and community members met at Lawrence High School Friday night for a vigil, at the same time people filled Viloria-Paulino’s home offering food and condolences. At least 50 people filed into the home Friday night, where singing could be heard as family and friends held their own vigil.

Another vigil is planned for the teenager Tuesday night in front of City Hall, followed by a community conversation at a local cafe for “people to express their concerns and build a consensus as to how we can move forward,” according to the Facebook event page.

Harmacinski writes for The Eagle Tribune in North Andover, Massachusetts.