Matched the description

A breakthrough occurred eight days after the discovery of the couple’s bodies. Two hikers spotted a man matching the description of a bearded person near the crime scene. They alerted the National Park Services right away. Park rangers immediately arrested the man as he was crossing a bridge on Harper’s Ferry on September 21.

He had Geoff’s belongings

The man had Geoff’s green backpack and was even wearing his hiking boots. These were the only two items missing from the crime scene. Geoff’s belongings were still inside the backpack: a book, a watch, and a sleeping pad.
Also found inside the bag was a knife and a .22 caliber revolver. Later, the gun matched the one used to kill Geoff in a test by Pennsylvania State Police. The traces of blood on the knife also matched Molly’s AB type.