By Jessica Michele Herring (staff@latinospost.com) | First Posted: Oct 21, 2013 01:57 PM EDT

The cause of death of alleged James "Whitey" Bulger extortion victim was homicide by cyanide poisoning, according to MaryBeth Long, a spokeswoman for the Middlesex District Attorney's Office in Massachusetts. 

The medical examiner's office confirmed that Stephen Rakes, 59, of Quincy, Mass., died of acute cyanide toxicity in July and ruled his death a homicide. The office plans to seek more charges against William Camuti, 69, of Sudbury, Mass. due to the official autopsy report. Camuti has been charged with attempted murder for allegedly poisoning Rakes' iced coffee, as well as unlawful disposition of human remains and misleading police. 

Camuti confessed to putting potassium cyanide in Rakes' beverage, according to a testimony by a Massachusetts state trooper at a hearing in the Concord District Court on Sept. 10, CNN confirms. 

"He indicated that he had purchased two iced coffees. He did in fact purchase potassium cyanide, which had been delivered and stored," said Trooper Michael Banks.

Rakes only took one sip, saying the coffee tasted too bitter. Camuti then drove him around the cities of Waltham, Woburn, Burlington and Lincoln for a number of hours until he "succumbed to ... ingesting" the cyanide, Banks testified.

Camuti is being held without bail for 90 days after a judge deemed his release would not "reasonably assure the safety of any other person or community." 

Camuti and Rakes were business associates, and Camuti allegedly poisoned Rakes because Rakes owed him money. 

In a phone call on July 16, Camuti asked Rakes to meet him about a potential property investment. The investment was a ploy to get Rakes to meet him. That same day, surveillance video showed Rakes leaving the federal courthouse where he was attending Bulger's murder trial. Rakes was wearing the same clothing in which his body was found, authorities said. 

Camuti met Rakes in a McDonald's in Waltham, where Camuti allegedly bought two iced coffees, one adulterated with two teaspoons of cyanide, and gave it to Rakes. Potassium cyanide interferes with the body's ability to use oxygen, CNN reports, and exposure can be fatal. 

Camuti allegedly disposed of Rakes' body in a wooded area, where it was found a day later. 

Rakes had been a reported extortion victim of Boston gangster Whitey Bulger, and learned shortly before his death that prosecutors no longer planned to call him to testify. 

Bulger, an Irish mob leader, was found guilty in August on 31 of 32 counts, including drug dealing, extortion, money laundering, drug dealing and weapons possession. A federal jury also held Bulger responsible for the murders of 11 people.