Two northern New Jersey girls accused of threatening to kill their seventh-grade classmates in a video posted online have pleaded not guilty to several counts of making terroristic threats.

The Record reports both girls were arraigned Monday in family court. The judge ordered that they remain on home detention and electronic monitoring and also continued orders that bar them from their school and from contacting any of the victims.

The defendants' names are not being revealed because they are minors.

Witnesses have said that roughly a dozen students were named as targets in the video, which was posted on YouTube but has since been taken down.

In the roughly 20-minute video, one of the girls brags about being a good assassin and explains why she wishes harm on her classmates.

"I have special killing thingies for different people," she says.

"I think about killing her," she adds. "I don't know why she's annoying." 

No one was injured.

"I think all of us need to step back and realize we're dealing with 13-year-olds here,'' said Robert Galluccio, an attorney for one of the defendants.

He said children sometime "do stupid things.''

"What we're really into here is looking into what were the motives and whether there was ever any intention to carry this out,'' he said.

Paterson Mayor Jeffery Jones said Friday authorities had no choice but to take action. 

"The nation is in a very alerted and alarmed state," he told NBC 4 New York. "Until some of the more recent events nationally, most folks probably thought, 'It could not happen to me, my neighborhood.' And I think it just puts us all, and should put us all, in a place where we pay attention."

A status conference in the case was set for May 23.