What do you call??

[Rickref]

I've been reading this forum all season and finally decided to jump in. I have found this forum to be very informative and somewhat humorous at times. Some of you have formed very good relationships. I have had situations occur in games that have I previously read about in this forum and was able to administer them correctly because of it. Thanks. Here is a situation I'd like your opinions on. In a 7th grade girls club type game Team A is running an inbounds play under their basket. 4 girls line up along the free throw line, one steps back, and they lob the ball over the other three to her. While this is happening the other 3 girls interlock their arms. Illegal use of arms 4-24-9. Now is it just a violation or do you call a foul and on which one? I just called it a violation and told the coach as I passed him not to run that play again, ever. There was no contact as no girl tried to get through it, but if there was. Foul.. on which one. Thanks