【like a bull in a china shop】 —said of a rough or clumsy person who is very careless and often breaks things:
We told her it was a delicate situation but she went into the meeting like a bull in a china shop.
Note: The expression does not correlate in meaning with the phrase like a bull at a gate—used of somebody acting with unchecked violence or impetuosity:
Try to approach her the right way. she′s dead if scared of policemen and you will get nothing out of her if you go at it like a bull at a gate.