Verified answer

It's a kind of inversion.

In English as well,

The man said this.

"I'm tired," said the man.

This is inversion.

Of course, we usually say, "おまえ　あれ　みたか？"

but the speaker wants to put an emphasis on "みたか" and say the word as soon as possible.

Translation breakdown:

Omae おまえ　　you

ha　　　　は subject particle (missing)

mita　　　見た see

ka　　　　か question particle requiring a yes or no

are　　　あれ denoting surprise at the end of the sentence.

お前は見たかあれ？　　omae ha mitaka are?

Hope that helps.