NEWARK, N.J. (CBSNewYork) — It was an emotional day in court for the family of a New Jersey college student found murdered earlier this month.

Tears flowed on Tuesday, as family watched Sarah Butler’s accused killer plead not guilty.

Victor Butler held his wife as she wiped away tears and watched 20-year-old Khalil Wheeler Weaver face charges in their daughter’s murder.

Butler, 20, of Montclair was found strangled to death in the West Orange section of Eagle Rock reservation on December 1.

The student had been missing for more than a week.

Wheeler-Weaver was arrested for murder, and disturbing of human remains last Wednesday.

The accused wore a black stare as defense attorney Diane Carl entered a plea of not guilty to all charges. It was in stark contrast to the family’s cries of desperation.

Butler’s father called out for answers.

“Why’d you do that?” he said.

Speaking exclusively with CBS2’s Ali Bauman outside of his family’s Montclair home, Victor Butler said he’s been conflicted since his daughter’s death.

“It’s been tough. I’m like torn between being violently angry, and being hurt by the death of my daughter,” he said.

Investigators believe his daughter met up with her accused killer several times the night she went missing. Butler’s father told CBS2’s Bauman he still doesn’t know how they met, and didn’t think she had a boyfriend.

“Never, never, never seen him a day before in my life,” he said.

Butler’s individual case might be close to a resolution, but her father believes there is much more to the mystery surrounding the suspect. He said since Wheeler-Weaver was arrested, he’s been contacted by another woman who claims she survived similar abuse from the same man.

“She saying something happened with her, with this same guy and it went undetected. It is ongoing and I don’t want to jeopardize what they got going on,” he said.

Wheeler-Weaver is being held on $1-million bail or cash bond. Butler’s funeral is set for Friday.

The Essex County prosecutor said their investigation is ongoing and could not confirm any other claims against the accused.