Iron Golem Strange Behaviour

When I walked up to an Iron Golem in my village it started attacking nothing. Hitting the air when there was no hostile mobs. I wasn't even attacking me.

What I expected was the normal behaviour of the Iron Golem.

(How I can recreate it) 1. Go to an Iron Golem.
2. It starts recreating what I described above.

Thank you very much, Happy New Year :=)