ND vs Temple

[BigTex]

Disclaimer: I'm a baseball guy.

Can somebody please clarify the rule for me. Is it the player behind the arc cannot cross the arc before the ball hits the rim, or is it that the player behind the arc cannot cross the free throw line before the ball hits the rim?

If it is the arc then it is a very clear violation. If it is the free throw line, then it is pretty close. He appears to have one foot down, just over the free throw line when the ball hits the rim, not "near the block" as somebody mentioned earlier.