Stewart, whom friends recalled as “a Jill of all trades” who loved the outdoors and working with her hands, died from strangulation and blunt force trauma, the state medical examiner’s office said.

Authorities did not say if there was any previous connection between Stewart and the teenager. The charge the teenager faces was not released by authorities because he is a juvenile.

The teenager was in Union when State Police took him into custody without incident on Wednesday night, the agency said. He was taken to the Long Creek Youth Development Center in South Portland.

It was not clear when the teenager would appear in court. Under Maine law, prosecution of juveniles in murder cases takes place in juvenile court until a judge approves a request from prosecutors to transfer the case to adult court.

A spokesperson for Attorney General Aaron Frey’s office, which is investigating, declined comment Thursday.

Stacey Lytton, a close friend who met Stewart some 20 years ago, said there is a “small sense of relief” that a person is in custody.

“But there is no comfort in the fact it’s a 17-year-old,” she said by text message. “Sunny’s murder was brutal and senseless. Her loss has left a hole in the hearts of everyone who knew and loved her and in the fabric of an entire community.”

“We are forever changed,” she added. “I hope we can continue to hold each other close and begin the long and painful path of healing.”

Shortly after 1 a.m. on July 3, authorities were called to Crawford Pond after Stewart did not return from paddleboarding the previous day. Officials have not said whether Stewart’s body was found on land or in the water.

During their search for Stewart, police had asked that anyone who may have seen Stewart paddleboarding on July 2 between 6 p.m. and 9 p.m. near 100 Acre Island on Crawford Pond to contact them.

Lytton, in an interview last week, said Stewart had a camper and was spending the summer at Mic Mac Cove Family Campground near the pond’s northern shore. She said Stewart had texted her in May to tell her about her plans.

“She said, ‘I’m a camper girl with camper dreams,’” Lytton recalled. “She was just so excited to be out there and be able to be on the water.”

“Who would do this?” Lytton said. “That’s the thing everybody says. Who would do this to her? It makes absolutely no sense.”

Her family has established a GoFundMe that has raised $33,000 as of Thursday.

“We’ve unexpectedly lost the light in our lives that was Sunny,” the family wrote.

Stewart lived about a half-hour from the pond, a popular summer destination about 80 miles northeast of Portland. The area is popular with campers and day-trippers.

The pond is approximately 600 acres and does not have public access. It is available for a variety of uses, including boating and fishing. The 100 Acre Island preserve in the center of the pond is a wooded island reachable by canoe, kayak or paddleboard.

Information from earlier Globe reporting was used in this account.

John R. Ellement can be reached at [email protected]. Follow him @JREbosglobe. Nick Stoico can be reached at [email protected].