Interception AND foul in the EZ

[Simbio]

Some friends and I have been going back and forth on this:

B1 intercepts in B's endzone and is downed there after scrambling around in the endzone. After the interception and prior to B1 being downed in the endzone, B2 blocks A2 in the back in the endzone.

Where would you mark the penalty off from and what would be the results of the play?

[Edited by Simbio on Nov 4th, 2004 at 01:17 PM]