SOUTHGATE, Mich. (Detroit Free Press)-- The first-period bell rang in Southgate's Davidson Middle School on Thursday morning.

A 13-year-old walked into an empty second-floor bathroom with a .40-caliber handgun. A single shot rang out about 8 a.m.

The teen, found by a schoolmate, had committed suicide with a gun that belonged to a relative, according to police.

The teen -- whose name was not released by school officials or police -- was rushed to a hospital, where he was pronounced dead.

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The suicide sent shock waves across the community, where more than 300 classmates, parents and school staff members gathered at Anderson High School on Thursday night, carrying candles and balloons. Classes won't resume until Monday, and counselors will be available.

The teen left behind a suicide note in his pocket. It was written as an open letter explaining that by the time it was read, he would be gone, Southgate Director of Public Safety Thomas Coombs said.

Coombs said the teen used the word "drama" to describe his life, but didn't offer specifics about the issues he was apparently having trouble dealing with.

According to the U.S. Centers for Disease Control and Prevention, suicide is the third leading cause of death for young people from 15-24, behind accidents and homicide. In Macomb, Oakland and Wayne counties, nearly 30 people younger than 18 have committed suicide since the beginning of 2012.

At the vigil, attendees marched briefly around the high school before gathering in a circle in front. In the bitter cold, there were words of thanks from the high schoolers who organized the event, a prayer and a poem. The teen's sister spoke briefly, carrying a family portrait of her, her two brothers, including the one who died, and their mother.

"You guys are so awesome," said the 25-year-old sister, in tears. "This is so amazing. Thank you."

Students at the vigil said talking about depression can be difficult, and while many said they had someone they could confide in, others said it is difficult to open up sometimes.

"Sometimes people are afraid to talk," said Kyra Goeller, 16, a sophomore at Anderson. She said people are worried that if they admit they are sad, they will be dubbed "crazy."

The teen, by several accounts given Thursday, was well-liked and a good student. Southgate Police Detective Sgt. David Fobar said there were no signs he was suicidal, and Southgate Community Schools Superintendent Bill Grusecki said there is no indication he was being bullied. Students agreed, and several said he was dealing with depression, but that he was always cheerful and happy at school.

Fobar said the troubles listed were typical for a 13-year-old.

"Obviously it was more to him, but I can tell you from raising kids, it was no more, no less than any other 13-year-old," Fobar said. "Unfortunately, it was how he chose to deal with it."

Jonae Mattison, 13, was one of several students who ended up in an auditorium during the lockdown Thursday morning. When she learned what had happened, and who was the victim, she was shocked. She came to the vigil with a dozen white balloons.

"He was smiling all the time," she said. "He was nice to everyone."

Classmate Nariah Chambers, 13, said the young man made their algebra class a joy.

"He just made it funnier," she said.

The teen's classmates have taken to social media as an outlet for their grief.

"I wish you knew how much we all love and care about you," one student said in a Twitter post.

"Just yesterday I hugged him," another tweeted. "I remember what he wore & he looked so happy. Now he's gone."

Thursday appeared to start out as any other for the 13-year-old.

A friend and his father picked up the boy at his home, Fobar said. The two boys had been friends since kindergarten.

"There was no indication that this day was any different from any other day for this young man," Fobar said.

Students described the harrowing scene at the school after the gunshot rang out, and the school was locked down.

Students scurried to the corners of classrooms, ran down hallways and were ushered to the gym before being released to parents and guardians.

Students told investigators that they heard a strange noise, like books falling, when the shot rang out. No one suspected gunshots.

But another student went into the bathroom and found the teen, who he thought had a head wound, Fobar said.

Eighth-grader Kali Timmis, 13, said she went to the corner of her English classroom.

"Wrecked, they're wrecked," she said of her classmates as she left the school with her mother. "There's crying."

Karina Moise, 14, went with her Spanish classmates to the gym.

"We just kept seeing people running down the hallway," she said.

The school does not have metal detectors, but officials will examine whether changes need to be put in place over the next few days.

"We had no idea that student was coming into the building armed," Grusecki said.

That a gun could get into the school shocked some parents, including Sheila MacNeil, 42, the mother of two students in the district. One of her children helped organize the vigil.

"At first it was panic, then sorrow," MacNeil said. "It's so close to home."

Investigators spoke to the teen's parents and plan to have a follow-up conversation to determine whether the teen had any mental health issues, Coombs said. An autopsy had not been performed yet Thursday, according to the Wayne County Medical Examiner's Office.

Family members present at the vigil said funeral plans are in progress.

At the teen's home Thursday, a man silently shook his head and gently shut the door, declining to comment.

"Our prayers and thoughts are with this family," Grusecki said.

Delaney Agee, a 13-year-old friend of the teen, said she often talked to him by phone. She said the two planned to go to a movie with other friends today. She said he never told her he was troubled.

"It didn't seem like anything was wrong," Delaney said. "Just to know that he is gone is really heartbreaking and shocking."

Staff Writers Gina Damron, Eric D. Lawrence and Lori Higgins contributed to this report.

More Details: Suicide prevention
If you or a loved one is thinking of suicide, call the National Suicide Prevention hot line: 800-273-8255. It will connect you with a counselor at a crisis center in your area 24 hours a day.

By Megha Satyanarayana, Tammy Stables Battaglia and Elisha Anderson