VANCOUVER, Wash. -- A homeless man accused in the stabbing death of a 13-year-old girl appeared in court Tuesday.

Clark County detectives said Darrin Sanford, a 30-year-old registered sex offender, killed Alycia Nipp sometime between 5 p.m. Saturday, when Nipp was last seen by friends, and 2:30 a.m. Sunday, when her body was found by her stepfather.

Deputies said Nipp's body was discovered in a field about 200 yards east of Northeast 13th Avenue in Vancouver. Sanford is known to camp in the area, police said.

A FOX 12 reporter spoke with Sanford Monday afternoon prior to his arrest. At the time, he said detectives had questioned him about the case, but determined he wasn't a suspect.

“They just asked me a bunch of questions because of my criminal history and asked me if I’m doing everything I’m supposed to do,” Sanford said.

When asked if he thought it was strange that Nipp would walk alone through the vacant lot, Sanford replied, "A little bit. It would."

Police initially released information about a person of interest, who was later identified as Sanford. After interviewing him, detectives said they had enough evidence to arrest him in connection with the killing.

Nipp's classmates at Thomas Jefferson Middle School said they were shocked upon hearing of her death Monday.

“There was a forward text message going around," said 14-year-old Sammy Graham. "But we didn’t believe it until we got online and then we saw it."

School administrators sent a letter home to families about the death. Meanwhile, Nipp's aunt said her niece "had a strength about her that none of us had."

"When we lost her, we lost our strength," Amber Hager said.

Neighbors who live in the area said the field where Nipp's body was found has always been off-limits to their children.

"All back behind the apartments, there are all kinds of bum camps and stuff going on back there," said William Dupuis, who lives in the neighborhood. "I won't let my children go back there … they're not allowed to go behind the apartments at all."

Hager said she finds it hard to believe that her niece would have gone into the field by herself.

"She's never done anything wrong. She's the most responsible teenager I know," Hager said. "This was totally unlike her to just go walking in the woods. She knew better."

Detectives are still investigating the case. Anyone with information on Sanford's whereabouts on Saturday and Sunday is asked to call 1-877-274-6311.