MILFORD -- His childhood friend dying in their school corridor, Christopher Plaskon dropped the knife and calmly walked to the principal's office at Jonathan Law High School, the police report released Tuesday states.

"I did it. Just arrest me," he told the school's resource officer.

Police said Plaskon confessed to stabbing 16-year-old Maren Sanchez to death at the school, and he now will stand trial as an adult.

Plaskon, 16, who classmates have said killed Sanchez on Friday because she wouldn't go to the junior prom with him, was arraigned on murder charges at a local medical facility.

The details of the killing were released as students returned to school Tuesday for the first time since the stabbing.

"Chris remains in the custody of the Department of Correction in the locked hospital psychiatric ward," his lawyer, Richard Meehan, said. "The name of the institution is being withheld, not only for his privacy but also that of the hospital staff and other patients."

Superior Court Judge Frank lannotti, who went to Plaskon's room at the facility with State's Attorney Kevin Lawlor, Meehan and a state court reporter, advised Plaskon of his constitutional rights, then made a finding there was probable cause for his arrest. He then ordered Plaskon held on $3 million bail.

According to the Milford Police Department's probable cause statement, about 7:10 a.m. on Friday, Officer James Kiely, the high school's resource officer, was called to the principal's office, where he saw Plaskon with bloody hands and clothing. The report states that Kiely, who knows Plaskon, asked him what happened and the boy confessed. Kiely handcuffed Plaskon, then went to the crime location in the hallway where he saw Sanchez was in grave condition.

The report says a teacher saw Plaskon on top of Sanchez during the attack and unsuccessfully tried to pull him off her. Another witness pointed out the bloody knife to officers where Plaskon dropped it, a short distance down the hallway.

The judge ordered Plaskon placed on a suicide watch and noted that he be allowed to take medication prescribed for him.

Plaskon is due in court in Milford on Friday morning. At that time he is not expected to enter a plea. Instead, the judge will set a date for a probable cause hearing.

So much purple

As students at Law headed back to class on Tuesday, still shaken by the events of Friday morning, they were surrounded by therapy dogs, grief counselors, police officers, firefighters and scores of city officials.

They had no shortage of reminders of the tragedy when they arrived at school. Media trucks packed the side streets adjacent to the Law High. Most of the students wore purple, and purple ribbons and balloons seemed to be everywhere, too.

"So much purple," tweeted a student.

"We had a great showing of support by many, many members of the community throughout the school day," said Mayor Benjamin Blake, who was in the school throughout much of the morning. "It was as normal a start to the school day, at least from my estimation, as they could have had. But they are still shaken. The entire city is still shaken."

Blake said that the canines at Law High were there to soften the shock.

"There were therapy dogs, and their handlers, in force," Blake said. "We also had members of our human services agencies there, too."

Principal Fran Thompson set in place a full eight-period schedule so the students would be in contact with most of their teachers. Also, the junior class, the class of the victim, met together for Period 8 on Tuesday.

Thompson told the students they would have to rely in one another to get through these next few days.

"The teachers will need you, and you will need them," he said. "We all feel sad and angry and guilty and confused, and that's OK," he said.

There was one sign of normalcy: Lunch selections were a turkey, ham, and cheese panini or a pizza bar with a choice of salad.

But it will be a long time before things are really normal again.

Calling hours for Sanchez will take place Thursday from 2 to 7 p.m., at the Cody-White Funeral Home, 107 Broad St. A shuttle service will be available beginning at 4 p.m. from the Parsons Complex about four blocks away. There will be no services.

On Monday, friends of Sanchez asked that students wear their prom dresses and tuxedos to her calling hours Thursday, according to a Twitter feed from the Jonathan Law High School newspaper, The Advocate.

Law students, their families and staff members were invited to a free showing at 6:30 p.m. of the movie "Heaven Is For Real" at the Connecticut Post Mall movie theater.

City Hall announced that because of the tragedy, the Mayor's Youth Award Ceremony, scheduled for Thursday, has been postponed. A new date will be announced in the near future, officials said.

A memorial fund has been established in the victim's name: the Maren Sanchez Memorial Fund, c/o Atty. Mike McCabe, 23 Sunnyside Court, Milford, CT 06460.