Monday was the first day back at school for classmates of a slain 13-year-old found in a Fairfield park Friday.

The girl's naked body was found at Allen Witt Park Friday morning where's there's now a growing memorial of flowers, teddy bears and candles for the 13-year-old girl.

Investigators are searching for girl's killer, but they have remained silent in terms of releasing any informationon on her death.

But they said they are making progress in the investigation, following some leads and eliminating others.

"We're fairly confident that what happened had nothing to do with the school, any school property or any school related activities," said Fairfield police Sgt. Robert Lenke.

The 13-year-old girl was a student at Green Valley Middle School and lived with her foster parents in Suisun City a few miles away.

Monday was the first day back at school for classmates of the slain teenager.

Grief counselors were on hand to help students cope with the loss of a classmate.

"It was a sad day for a lot of kids," said Frankie Torres, a seventh grader.

"She's a really good person and she was a friend to a lot of us here so it's pretty bad," said Jordan Carrow, an 8th grade-student.

A spokesman with Alternative Family Services, that arranged the foster care, released a statement saying they're cooperating with authorities.

A cousin of the victim said a candlelight vigil will be held at the scene on Friday.