Offsides / Encroachment on kickoff

[stegenref]

I was working head linesman the other night in a JV game and on a kickoff one of the K players crossed the free kick line before the kicker kicked the ball. I blew my whistle to stop the play and threw my flag. The WH got the ball and tossed it back to me and told me to signal the penalty...I didn't know what to do. Should I...

• Turn to the pressbox.
• Raise my hand for a dead ball foul (signal #7) and say, "We have a dead ball foul..."
• Signal encroachment (signal #18), and say "...Encroachment..."
• Point towards the kicking team and say, "...on the kicking team."
• Say "Five yard penalty, repeat the kick."

It is encroachment, right? Not a false start.