Two men already held on charges they conspired to help the Islamic State group have pleaded not guilty to additional terrorism charges.

Nicholas Rovinski, of Warwick, Rhode Island, and David Wright, of Everett, Massachusetts, were charged in a superseding indictment with hatching a plot to kill a conservative blogger following instructions handed down by an Islamic State recruiter operating overseas.

Neither Rovinski nor Wright appeared in federal court Thursday. WPRI-TV reported (http://bit.ly/1rDqM3Q) lawyers for both entered not guilty pleas for them.

Prosecutors allege the two plotted with Wright's uncle Usaamah Rahim to behead blogger Pamela Geller, who is known for provoking Muslims. The plot was not carried out.

Rahim, who had been under surveillance, was killed last year by investigators who say he lunged at them with a knife when they approached him in Boston.

Rovinski and Wright were charged in June 2015 and pleaded not guilty to conspiring to provide material support to a terrorist organization.

Investigators say Islamic State recruiter and hacker Junaid Hussain communicated instructions about the plot directly to Rahim from overseas in May 2015. They say Rahim then told his nephew.

Hussain was killed in a U.S. drone strike in Syria in August. The U.S. military has said Hussain had been recruiting sympathizers in the West to carry out lone-wolf terrorist attacks.

Prosecutors said Rovinski, even from jail, tried to recruit people to help carry out plans for violent attacks in the United States, including to decapitate non-believers.

Geller last year organized a Prophet Muhammad cartoon contest that ended in gunfire in Garland, Texas, with two Muslim gunmen shot to death by police. She has spearheaded scores of events across the nation to decry Islamic extremism.