adding panel dynamically on button click

Question

I've a panel "txn_panel" which contains:

one label "lbl_particular", 3 textboxes txt_quantity, txt_rate, txt_amount.

When the Add button is clicked I want to add this panel dynamically i.e.

first time there will be only one label and three textboxes. On clicking the Add button the label and the textboxes should be added vertically. It should go for ten times. How can I do that?