ROUGH CUT (NO REPORTER NARRATION) Police in Delphi, Indiana on Monday released a sketch and video showing a man they suspect to have murdered 14-year-old Liberty German and 13-year-old Abigail Williams. Police Superintendent Doug Carter asked for the public's help in identifying the killer.

In February of 2017, police released an audio clip of a man's voice saying "down the hill" -- taken from video found on victim Liberty German's cellphone.

Also on the 14-year-old's cellphone, an image of a man walking near the hiking trail around the time the girls disappeared.

Police have been searching for a suspect in the deaths of Liberty German and Abigail Williams, whose bodies were found on Valentine's day near a hiking trail some 60 miles northwest of Indianapolis.

Police called German a hero for having the presence of mind to make a recording, even as danger lurked.

Officials hope someone may recognize the man in the video clip and come forward to help solve the crime.