The man accused of killing Chandra Levy in Rock Creek Park in 2001 has pleaded not guilty to additional charges of threatening to kill a witness, the Associated Press is reporting. Prosecutors filed the additional charges against Ingmar Guandique earlier this month, citing evidence that Guandique wrote a threatening note to the witness and had someone deliver it. The AP updates that Guandique’s lawyer entered a not-guilty plea for him to the new charges during an arraignment today in D.C. Superior Court. Guandique is already serving a 10-year sentence for separate assaults in Rock Creek Park, and is facing first degree murder charges in the death of Levy.