If the attacker knows that it's there, he may simply copy over it with itself.

"An attacker wouldn't even know you had a force here until your arrows gave him warning!"

Whoever they are, these attackers know exactly what they're doing.

He was sure the attackers didn't yet know they were coming.

And the attackers must have known that Vickers was there, probably they knew about the radio also.

The victim told the police that the attacker apparently knew her, although she was not able to identify him.

The Kurdish attackers knew who he was and wouldn't shoot him or his men.

The attack is especially dangerous when the attacker knows the format of the message.

That is, no attacker knows anything about the scheme the user could have used.

If the attacker knows what he is doing, very small becomes pretty close to nonexistent.