New Jersey Gov. Chris Christie says it is "reprehensible" for the National Rifle Association to run an ad bringing President Barack Obama's daughters into the gun-control debate.

The nationally prominent governor on Thursday criticized the ad, which accused the president of being a hypocrite for allowing his daughters to be protected by armed Secret Service agents but not embracing armed guards for schools.

Christie said children of public figures should be off-limits to political attacks.

The Republican governor also sided with the Democratic president when Obama came to New Jersey to tour storm damage in October. Christie's praise of the president six days before the election was sharply criticized by some GOP members, who accused Christie of helping to tip a close election to Obama.