Dynamic table with row insertion

I'm trying to make a form page separated in different tabs each representing a different phase. In one of the phase, i want a dynamic table which allows to dynamically insert records of a certain entity. To give some context, i'm working on a form which allows to file complaints and add witnesses to a crime. I took the liberty of providing a sketch in order to better illustrate what i'm looking for:

And there's also this example i found on JSFiddle: http://jsfiddle.net/leftstick/DVEXG/

Essentially, i want a table which adds a new row everytime you fill the inputs and click the plus button. How can i achieve this?