Wiktionary
turn loose
vb. (context transitive idiomatic English) To release or let go; to permit (someone or something) to roam freely or to act freely.
Usage examples of "turn loose".
Then turn loose the Jersey Special mosquitoes, the yellow jackets, the hornets, and all the other flying pests on hand except the giant bumblebees.
But let him find out that we killed the prisoners, if we do kill 'em, and Savage will turn loose with everything.
Now they're not going to turn loose a lot of it when a little high-handed banditry would make it unnecessary.
You boys take my advice and turn loose that squaw, and Kahtenny might just ride off and leave you be.
If you want to get out of here alive you'd better turn loose his squaw.