Something doesn't belong

On a walk with my wife yesterday, we came across a vest and backpack that had been left on a boardwalk in a wooded area. It's just off a main street in Fairfax, but the trees are dense in this area and it's lower than street level, so it can't be seen from the road even though it's in the middle of the city. I reported it to the police in case it was left by someone who needed help, but I'll probably never know the outcome. Several reasons I can think of for it being there early in the morning and none of them are happy scenarios. Here are a few photos I took.​
​

This is the view from street level.

Viewed from the boardwalk.

I managed to also catch my shoe in this photo.

The backpack and vest are barely visible from this distance. They are at the bottom of the fence near the top of the photo.