Darci Day shares her sorrow over the death of Elaine O'Hara.Darci Day/YouTube

Darci Day, a young American woman who could have become a victim of convicted murderer Graham Dwyer, took to Twitter on Sunday evening to send a heartfelt message of sorrow for the loss of Elaine O’Hara.

Dwyer, aged 42 and a father of three, was found guilty of the murder of Elaine O’Hara last Friday following a ten-week trial during which Darci testified against him.

Darci, who first met Dwyer on a fetish website in 2010, took to social media to express her sorrow for the victim. "RIP Elaine. Wish I knew you and could have saved you," she said.

"Poor Elaine she didn't deserve that. She deserved to be loved."

The 26-year old also spoke about the difficulty of giving evidence during the trial tweeting, "Don't let the darkest of human nature win; let beauty and light shine through the pain. There is a lot of good in ppl #grahamdwyer."

Darci had previously tweeted her relief following the verdict announcement on Friday: “I'm glad justice has been done for all the families and my heart goes out to everyone involved.”

“There is a very strong message of hope and love I want to send to anyone who has felt broken or depressed or suicidal and that message is they are loved and beautiful.”

“And the Lord loves them. This has been a very long painful trial,” Darci said.

Graham Dwyer found guilty of the murder of Elaine O'Hara in 2012. Photo by Photocall Ireland.

Graham Dwyer found guilty of the murder of Elaine O'Hara in 2012. Photo by Photocall Ireland.

Darci, who lives in Maine, gave shocking video evidence during the murder trial, telling the jury of Dwyer's advances and his desire to kill her. Darci and Dwyer began their online communication in 2010 when Darci joined fetish website darkfetishnet.com. The pair had not been in contact since 2011 until Dwyer, having acquired Darci’s home address, sent her a Christmas card this year, just a month before the murder trial was due to start.

In the card, Dwyer protested his innocence, claiming that there was no evidence against him and that he was being blamed for a suicide.

The court had previously disallowed Darci’s requests to present evidence to the trial via video despite her fears of appearing in the same room as Dwyer. Following the arrival of the Christmas card, however, Mr. Justice Tony Hint felt that there was no other explanation for the renewal in contact after three years other than an attempt to influence Darci and her evidence and so allowed her evidence to be presented by video link.

Darci, who began talking to people online about her suicidal thoughts when she was 14 years old, joined darkfetishnet.com when she felt that death was the only option left to her to escape the torment of her troubled upbringing. It was here she met Dwyer, an architect, with whom she spoke on the phone about his graphic plans to kill her when she felt that she could not do it herself.

In a document entitled "Killing Darci," recovered from Dwyer's computer and presented during the trial, Dwyer detailed how he would fly Darci to Ireland, take her to a cabin where he would cut her throat as he raped her, and then have sex with her mutilated corpse.

During these conversations, Dwyer also mentioned former childcare worker Elaine. Dwyer told Darci that he was in an intimate relationship with Elaine and that she was also suicidal. In her evidence, Darci testified that Dwyer told her Elaine had asked him to kill her and that he had previously cut her.

Police investigate the scene where the remains of Elaine O'Hara were found. Photo by Photocall Ireland.

Police investigate the scene where the remains of Elaine O'Hara were found. Photo by Photocall Ireland.

The remains of Elaine O’Hara, 36, were found in a forestred area on Kilakee Mountain, Rathfarnham, Co Dublin, in September 2013 following a thirteen month search for the missing woman. Thanks to a drought in the summer of 2013, vital evidence linking Dwyer with O'Hara, including keys, phones, sex toys and rope, was discovered in the Vartry reservoir just 15 miles from the murder scene.

O'Hara had been released from psychiatric care just hours before the murder. Dwyer was convicted of killing O'Hara on August 22, 2012 last Friday and remains in Cloverhill Prison until he is sentenced next month.