A couple of my rabbits go for the dust pan and broom. It could have been in reaction to your “invading” his space or your hand in his blind spot directly in front of the nose. That is pretty common. He’s hasn’t reacted badly before when you’ve cleaned out his space when he’s in it?

Some other things that may make a rabbit more grumpy:

 – Moulting or right before a big moult.

– Spring. This can cause a small hormone surge even in desexed rabbits.
– The smell of another rabbit. If you’d handled another rabbit before attending to him, he could react to their scent.

– Underlying health issue. If you;re planning to have him neutered, have the vet do a full health check to rule out anything that could be causing pain or irritation.

Maturity and behaviors associated with it can come at different times. Wick’s first hormonal behavior occurred at 9mo when he started spraying, and even after his neuter that month, he’s now 1.5yrs old and he’s just now started digging.

I agree with jg that other health issues should be considered as well, as sudden aggression is a good indicator of pain. Any changes in poop, pee, or appetite/energy?

My neutered boy used to try to kill the dust pan and mini broom if I used it in his cage. He just really hated that thing.