DERRY - A Portsmouth woman was arraigned on charges for hindering the prosecution of a murder in Derry District Court this morning.

Kathryn McDonough, 19, of 450 Greenside Ave., Portsmouth, was arrested on Christmas Eve and charged with one felony count of hindering apprehension or prosecution and one felony count of conspiracy to commit hindering apprehension or prosecution related to the disappearance and alleged murder of University of New Hampshire sophomore Elizabeth “Lizzi” Marriott, 19, in October.

Police allege that McDonough provided a false alibi for her and boyfriend Seth Mazzaglia, 29, of 1 Mill St., in Dover when questioned Oct. 12 about Marriott's disappearance.

Mazzaglia was charged with second-degree murder on Oct. 13 for allegedly strangling and/or suffocating Marriott in his Mill Street apartment on Oct. 9, the last night she was seen alive.

Documents related to his arrest have remained under seal per an order by Dover District Court Judge Stephen Morrison as the state seeks to indict Mazzaglia on the charge.

Mazzaglia was arrested on Oct. 13, the day after police began searching the waters around Peirce Island in Portsmouth for Marriott's body based on “credible information.”

Although the search has continued for the last two months, Marriott's body has not yet been recovered.

The night she disappeared, Marriott had sent a text to a friend saying she was going to meet another friend, believed to be McDonough, in Dover. Sources have confirmed to the New Hampshire Union Leader that McDonough was Mazzaglia's live-in girlfriend at the time of the alleged murder.

On Wednesday, McDonough was arraigned on the two charges filed against her via video arraignment in Derry District Court. Her bail was set at $35,000 cash or corporate surety. The courtroom was filled with members of McDonough's family including her parents, grandparents and aunts and uncles according to Attorney Jay Nadeau, who is representing the McDonough family. McDonough is being represented by attorney Ryan Russman of Exeter. Nadeau said the family wanted to show their support for McDonough.

According to court documents, on or about Oct. 12, McDonough gave investigators a false alibi regarding her and Mazzaglia's whereabouts on the evening of Oct. 9 and provided false information regarding their lack of interaction with Marriott that night.

Police also allege that McDonough conspired with Mazzaglia to provide the false alibi. According to court records, on Oct. 12 in Newington, Mazzaglia and McDonough both provided police with the false information.