Intentional foul question

[dpk933]

Time is running out in a close game. Team A is trying to foul to stop the clock. B-2 inbounds the ball to B-1 after a basket by Team A. As B-1 winds up to throw a full court pass to B-3, A-1 hits B-1's arm on the pass. B-1 falls to the ground. Official calls an intentional foul on A-1. B-3 hands the ball to the official. Team B coach tells B-3 to shoot the free throws.

Question: Who shoots the ball on an intentional foul? B-1 or B-3? Does this fall under Rule 8? Can anyone? Any rule references would be appreciated. Thanks!