The parents of missing University of Virginia student, Hannah Graham, released an emotional plea for information on Saturday, as the search for their 18-year-old daughter extended into its fourth week.

“Somebody listening to me today either knows where Hannah is, or knows someone who has that information,” said Sue Graham in the taped statement, according to the Associated Press. “We appeal to you to come forward and tell us where Hannah can be found.”

John and Sue Graham released both a written and taped statement to the media. In the video, Sue Graham reportedly fought back tears as she read the statement in a shaky voice.

“John has already said that this is every parent’s worst nightmare,” said Sue Graham. “Please, please, please help end this nightmare for all of us. Please help us to bring Hannah home.”

The search for Hannah Graham has been ongoing since she was reported missing on September 14. Although a suspect, Jesse Leroy Matthew Jr., has been arrested and charged with “abduction with intent to defile,” Hannah still has yet to be found. The AP reports that a team of about 110 people including law enforcement officers and trained volunteers continues to search through the fields and countryside surrounding Charlottesville.

In their statement, the Grahams thanked everyone who had contributed to the effort.  

“To each one of you who made the effort to call in with information, we express our heartfelt thanks. We also thank all of you who have actively searched your properties and reported the results to the police. However, despite all your efforts, Hannah is still missing.”

The statement marks the first time in nearly two weeks the Grahams have publicly commented on the case.