Mr Melchert-Dinkel has not publicly commented on the case
A former US nurse has been charged with two counts of aiding suicides on the internet, US officials say.
William Melchert-Dinkel, 47, is accused of encouraging the suicides of Briton Mark Drybrough, from Coventry, in 2005 and Canada's Nadia Kajouji in 2008.
Mr Melchert-Dinkel from Minnesota allegedly posed as a female nurse, instructing people in suicide chatrooms how to take their lives.
He reportedly admitted helping five or fewer people kill themselves.
The criminal complaint filed in the case in Rice County, Minnesota, said Mr Melchert-Dinkel had told investigators that he encouraged "dozens" of people to commit suicide for the "thrill of the chase".
Prosecutors argue that he posed as a female nurse - using nicknames "Cami", "Falcon Girl" and "Li Dao" - and pretended to feel compassion for people contemplating suicide in chatrooms. He is believed to have entered suicide pacts with some prospective victims.
The suicide victims were encouraged to kill themselves, it is alleged
The complaint mentions two people: Mark Drybrough, 32, who hanged himself in Coventry in 2005, and Nadia Kajouji, 18, who drowned in 2008 in a river in Ottawa.
Mr Melchert-Dinkel reportedly offered some victims detailed instructions how to commit suicide.
The complaint said he had told police he stopped using internet chatrooms shortly after Christmas 2008, because he "felt terrible" about his role as an advocate for suicide.
Mr Melchert-Dinkel has not publicly commented on the charges. He is due to appear in court on 25 May.
Some legal experts say it could be difficult to prosecute Mr Melchert-Dinkel under a rarely used law because he allegedly only encouraged the victims to kill themselves, without physically helping them to take their lives.