A protester holding up a sign is removed by a security guard during a speech by Wayne LaPierre (unseen), executive vice president of the National Rifle Association (NRA), during a news conference in Washington December 21, 2012. REUTERS/Joshua Roberts

WASHINGTON — The head of a pro-gun group often at odds with the National Rifle Association is warning Americans not to shoot the messenger.

On Friday, the powerful NRA made the case publicly for armed guards in every school to prevent future tragedies like last week's horrific school massacre in Newtown, Conn., when Adam Lanza, 20, opened fire on Sandy Hook Elementary School, killing 20 children and six adult staff members.

The suggestion was followed by a deluge of criticism from gun-control advocates and politicians who blasted the organization as tone-deaf and out of touch.