It was a very nice day and lots of people were out, except this small part of the trail.
http://arlington-va.patch.com/articles/police-four-mile-run-trail-stabbing-victim-remains-hospitalized
http://www.wusa9.com/news/virginia/article/262082/188/Woman-Stabbed-On-Bike-Trail-In-Arlington
http://www.nbcwashington.com/news/local/Woman-Attacked-on-Arlington-Trail--209789851.html
http://www.wjla.com/articles/
http://www.wtop.com/139/3346633/Suspect-at-large-after-stabbing-woman-on-Arlington-trail