Girlfriend of murder suspect Mazzaglia arrested in N.H. Marriott case PORTSMOUTH, N.H., Dec. 26 (UPI) -- The girlfriend of a suspect in the disappearance and death of a New Hampshire college student was arrested on Christmas Eve for giving alleged false alibis. Kathryn McDonough, 19, of Portsmouth is accused of hindering apprehension or prosecution and conspiracy to hinder apprehension or prosecution in the Oct. 9 disappearance of of University of New Hampshire student Elizabeth "Lizzi" Marriott, 19, of Chester, Foster's Daily Democrat (Dover, N.H.) reported Wednesday. Bond was set at $35,000, Foster's reported. Marriott's alleged killing occurred during a sexual encounter, the newspaper said sealed court affidavits allege. Marriott's body was never found, but prosecutors say they have credible evidence that Seth Mazzaglia killed the woman in his apartment the night she disappeared. McDonough was living with Mazzaglia, 30, of Dover. Assistant Attorney General Peter Hinckley said in Derry District Court McDonough provided police a false alibi for herself and Mazzaglia for the day Marriott is believed to have been killed -- and the dead woman's body is still missing largely due to McDonough's false statements, the newspaper said. Mazzaglia was arrested on Oct. 15 and charged with second-degree murder in Marriott's death. Mazzaglia is being held without bond. He allegedly strangled and suffocated Marriott.