Maine man accused of sending cyanide to suicidal person

BANGOR, Maine -- A Maine man who allegedly mailed poisonous potassium cyanide to a suicidal Englishman who used it to kill himself was arrested on Wednesday, court documents show.

Sidney Kilmartin sent the poison to Andrew Denton, of Hull, England, in 2012, resulting in Denton's death, papers filed with the U.S. District Court said.

Kilmartin's indictment alleges that he mailed the poison "with the intent to kill or injure another."

British authorities investigated in conjunction with American agents after learning Denton, 49, had ordered the cyanide over the Internet to commit suicide after struggling with depression, according to a report last year in Denton's hometown newspaper.

Potassium cyanide is a highly toxic, colorless salt often used in gold mining and electroplating, and exposure to it can be rapidly fatal.

Kilmartin's attorney, Jeffrey Silverstein, told CBS News' Crimesider that Kilmartin has been in the custody of the Commissioner of the Maine Department of Health and Human Services since 2009, when he was found not criminally responsible -- a finding similar to insanity -- on 2007 assault charges.

Though Kilmartin was under care of the state, by 2012, when the cyanide was allegedly mailed, he was no longer under 24-hour supervision, according to Silverstein.

"I understand he was granted some measure of independent living," Silverstein said.

Kilmartin is charged with mailing injurious articles and mailing injurious articles resulting in death, the latter carrying a maximum penalty of life in prison upon conviction. The next hearing in his case is scheduled for Nov. 14.