Paper.js – how to get a list of all items inside a bounding box?

I want to allow the user to drag a rectangle around the desired items, to select multiple Paper.js items at once.

For individual item selection by clicking, I can do a hitTest which returns whatever element is under the cursor (if any).

I have already written code to draw a selection rectangle with the mouse.

But how can I get a list of all items that are inside the rectangle? Do I have to iterate all items on the project and determine if their bounding boxes fall inside the selection rectangle? or is there some built-in function to do this?

hitTestAll seems to only return the items directly under a point (if multiple items are stacked), right?