In sporting and military battles, when you are injured you are literally **carried off the field**.  In the example it's not clear whether they were actually injured, or whether the speaker is worried that they might be.

Note that the grammar in your example is a kind of abbreviated style common to spoken military and police.

The following examples have the same meaning.

* Example: **People find out X, there's going to be Y**
* Fuller: **If** people find out X, there's going to be Y
* Fullest: **If** people find out X, **then** there's going to be Y