WWII anecdote: white towels at a command post allegedly drew artillery, killing three

What was said

"But finally, a few of the men apparently forgot or disregarded their instructions and hung out a couple of white towels to dry and sweatshirts also. As a result, RCP drew enemy artillery fire, costing the lives of three men."

Willink reads an account attributed to a 135th Infantry soldier describing how visible items—white towels and sweatshirts—were hung out at a command post despite warnings about concealment. The narrative says the position then drew enemy artillery fire which killed three men.