Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

PENSACOLA, FL — Donald Trump on Friday told a packed crowd that Democratic rival Hillary Clinton could "shoot somebody" and not be prosecuted, in an attack that echoed a boast the businessman once made about himself.

"She could walk into this arena right now and shoot somebody with 20,000 people watching," Trump hypothesized, miming a gun with his fingers. "Right smack in the middle of the heart, and she wouldn’t be prosecuted, okay? That’s what happened. That is what's happened to our country."

The line was reminiscent of a comment Trump made during the primaries, when he told his supporters he could stand in the middle of Fifth Avenue in New York and shoot somebody and it wouldn’t cost him any votes.

Trump has criticized an FBI decision that recommended no charges for her use of a private email server while secretary of state. The FBI director this week defended the decision as not a close call, and said there was no prosecutable case.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Related: Mike Pence Releases 10 Years of Tax Returns

Reading from a prompter but diverging, as he often does, from his prepared remarks, Trump had another violence-related comment ready for the raucous and passionately pro-Trump crowd.

"With Iran, when they circle our beautiful destroyers with their little boats and they make gestures at our people, that they shouldn’t be allowed to make, they will be shot out of the water," Trump promised. The arena filled with cheers.

Trump's promised actions against Iran would be an effective declaration of war. Minutes earlier, Trump advocated for a foreign policy that was based on three key words: "peace through strength."

Trump’s remarks reference an incident days earlier when Iranian ships harassed an American Navy Patrol Ship in the Persian Gulf and nearly cause a collision with the U.S. ship.

Throughout his remarks, Trump attacked Clinton for being "trigger happy" on foreign policy and painted her as someone looking to recklessly embroil the United States in foreign wars. Trump asserted that her policies have yielded "death" and "destruction."

The Republican nominee took it one step further, bluntly and without evidence, stating: "Personally, I think she's an unstable person." Trump has repeatedly questioned Clinton’s mental stability and health throughout the general election, in tandem with dog whistles about her "strength and stamina."

Related: 'Make America Great Again' — Who Said It First?

The rally — both in crowd size, enthusiasm, and Trump’s signature off the cuff riffs — was reminiscent of a Trump not often seen on the campaign trail anymore.

Since shaking up his campaign senior staff, Trump has been on message and with a prompter at almost all of his public appearances and rallies. As he’s grown more comfortable, however, the Republican businessman has started ad libbing more frequently.

Among those ad-libs, a revival of his antagonistic comments towards the press. “Why don’t you show the arena, fellas?” Trump said to the press lining a riser at the back of his event. “Turn those cameras.” The goading request of press to show the crowd was once an expected chorus from Trump, but has since dissipated with the use of prepared remarks. The crowd responded in kind, booing press.

The campaign does not allow a cuts riser for press, making crowd shots more difficult.