The bloody past of National leadership contender Mark Mitchell

For five days in 2004, Mark Mitchell was perched on the roof of an Italian diplomatic compound in the Iraqi city of Nasiriyah, being shot at by rebels. 

He was working for private British security firm Control Risks as a soldier and hostage negotiator, and was armed with machine guns and AK-47s. 

Surrounding the compound were 2000 insurgents from Shia-leader Muqtada al-Sadr's Mahdi Army, who bombarded and attacked the area for the duration of the five-day raid. Most of them were killed or retreated.

"There was exchange from both sides," Mr Mitchell told Newshub exclusively. "We were literally fighting for our lives.

"They were trying to get into the compound. It was a very small compound.

"We were under indirect fire attack, which means mortar attacks, RPG and small arms."

It wasn't just the Mahdi Army firing shots. The coalition forces defending the compound were firing as well, including Mr Mitchell, who was embedded with them.

"I was involved in engagements with the enemy without a doubt," he says. "There were definitely some heavy casualties".

Mr Mitchell admits shooting at the insurgents, but he refuses to "physically confirm" if any of them were killed.

"That's what happens when you're in an engagement like that, that's right," he says carefully. 

How many of the 2000 rebel soldiers did he kill? He won't say.

"All I'm going to say is that we were attacked, it was a determined attack, and we had to defend ourselves and that's what we did.

"It was a very intense period of time for all of us who were involved in that," he says.

"I saw some incredible acts of heroism and courage and bravery, but I'm not going to get too much into the detail on it".

Mr Mitchell says if the insurgents had won the siege, he'd be dead, alongside most of the Italian, British and American troops and diplomats.

"If they had got into the compound, it's highly unlikely anyone would have survived."

So what's it like being shot at?

"You don't give it much thought at the time. The stakes were pretty high.

"We had Italian, American and British diplomats with us that we were responsible for protecting."

Mr Mitchell says while he won't actively promote his nine years in Iraq as part of his leadership campaign, it doesn't mean he's trying to hide it.

"I think it's a very positive thing, and I'm very proud of everything I did overseas and proud to have served alongside the people I did."