After the 1st half buzzer.

[RogersUmp]

I saw this at a 5th grade/11U girls game this last weekend. Player A1 brings the ball aross halfcourt and desperately tries to launch a shot before the clock runs out but her shot is clearly a second or two after the buzzer. In the act of shooting Player B1 hip-checks Player A1 into a heap on the floor. One official said he saw nothing and the other said it was after the buzzer, I have nothing.

What is the correct call? Do you consider ejecting B1 for unsportsman-like conduct? Is there a foul if it's a) after the 1st half buzzer b)end of game?