American authorities say a male nurse, who is suspected of encouraging an 18-year-old Carleton University student to kill herself, used the Internet to counsel others to also take their lives.

Police allege 46-year-old Minnesota resident William Francis Melchert-Dinkle was involved in suicide conversations over the Internet with at least one person outside the United States.

Although they have not charged him with any crime, Melchert-Dinkel's involvement with Nadia Kajouji is being investigated after police reviewed a transcript of an online conversation he had with Kajouji just prior to her disappearance.

The Brampton teen disappeared from her university dorm room in Ottawa last March. Her body was pulled from the Rideau River one month later.

The Media Awareness Network says although many people seek help online, they must be aware of the risks associated with online relationships.

"The biggest problem when you're looking for help online is that you don't know the qualifications or the intentions of the person that you're talking to," said spokesperson Jane Tallim.

"Our research has indicated it doesn't take long for trust to develop in social networking and instant messaging relationships."

Tallim says parents need to talk to children of all ages about their online relationships and make sure they know that the people they're talking to might be concealing their true identities.

"As parents, we have to realize that our kids have access to a whole world of information for any sensitive issue that they may not feel comfortable coming to us with. With all the stigmatization associated with mental health difficulties, it can sometimes be hard for young people to approach people in their own lives about questions," Tallim told CTV Ottawa.

Nadia's father Mohamad Kajouji has said he saw police transcripts that show his daughter went online to talk about her depression and she believed she was talking to another suicidal woman.

He said the person his daughter was talking to wanted her to hang herself in front of a webcam.

"For somebody to do that to a human being like that, asking her to get a rope and herself on camera so he can watch her die; I just cannot believe a human being could do that to another human being," said Kajouji, who fought back tears while talking to CTV's Canada AM Friday morning.

According to a recent study, Tallim says 45 per cent of teens go online looking for help to deal with anxiety, depression or stress.