Phil Robertson, one of the stars of the "Duck Dynasty" reality TV show, says Islamic militants waging a campaign of war and terror in Syria and Iraq either need some Jesus or need to be killed.

"In this case, you either have to convert them, which I think would be next to impossible. I'm not giving up on them, but I'm just saying either convert them or kill them," Robertson said on the Fox News show "Hannity" on Tuesday night. "One or the other."

Robertson compared ISIS to "street gangs, street thugs on steroids" and said "we're going to have to deal with this group way more harshly than we have up to this point."

"Because they're so harsh," host Sean Hannity added. "I know there are going to be people always looking to jump on you and say 'convert them or kill them,' and they're going to say 'there goes Phil Robertson again.' I know the media. I know how they act."

Robertson said his first choice is Jesus.

"I'd much rather have a Bible study with all of them and show them the error of their ways and point them to Jesus Christ," Robertson said. "However, if it's a gunfight and a gunfight alone, if that's what they're looking for, me personally, I am prepared for either one."

Robertson had a Bible with him on the set and quoted scripture throughout in the interview. However, it's not clear which passage he may have been referring to with his call for conversion or death.

ISIS militants have carried out forced conversions of their own while taking control of towns with non-Islamic populations and killing those who have refused. In some cases, women of other faiths have been ordered to not only convert to Islam but also leave their husbands and marry jihadi fighters.

Members of other faiths have also been fleeing from their homes as Islamic militants advance on their communities.