The three friends began partying with extra-pure heroin and Alpharetta police said the 20-year-old woman overdosed almost immediately. Her two “friends” spent next 10 hours waiting to see if she would wake up.

After Chelsea Bennett was dead, 911 was called. Paramedics took the corpse of the Johns Creek woman to the hospital.

That was in March. A murder indictment was returned this month. Her parents are demanding justice.

“The news that her life was so tragically taken is heart-breaking,” the family said in a prepared statement Thursday. “Chelsea-Ivanna was a gracious gift and we cherished her.”

On July 15 a Fulton County grand jury returned murder indictments against the man who is accused of selling the heroin and the man who is accused of injecting the woman with the drug.

A third man was indicted for concealing a death.

The defense attorney for one of the men, Cory Ben-Hanania, called Bennett’s death a tragedy for all families involved.

“My client was devastated when this happened,” said Thomas Salata, the defense lawyer. “He’s devastated still. They were best friends.”

Alpharetta Public Safety Director Gary George said he, his detectives and Fulton County prosecutors were pursuing the rare murder charge in drug overdose case to send a message to the public.

“We need to prosecute,” he said. “If we could take it to a drug cartel in another country, we would do that.”

He noted there had been a spike in heroin-related deaths nationwide because the drug now often has purity levels of 70 to 80 percent while during the heroin epidemic four decades ago the purity level was often no higher than 10 percent.

The police investigation concluded the sad saga started on the early morning hours of March 3 when Ben-Hanania left his parents’ home on Ridge Oak Place with Bennett and another friend, Sebastian Andrade. They went to Marietta to buy heroin from Kevin Robert McCaffrey, police said.

By 4 a.m. they had returned to the house on Ridge Oak Place. Shortly later they were calling McCaffrey, saying Bennett had overdosed. Take her to a hospital, McCaffrey told them, police said.

Instead, police said, the two destroyed evidence and discussed alibis.

“Kevin McCaffrey actually sold the drugs,” said Det. Dave Bochniak, one of two detectives who investigated the death. “Cory injected the heroin into her. She almost immediately had an issue. They were aware she had overdosed.”

Bennett’s family was frantically looking for her and eventually tracked her to the Ben-Hanania’s residence, which they called around 2 p.m. that day.

Ben-Hanania’s brother searched the house and finding her called for an ambulance but Bennett was already dead, Bochniak said.

Andrade was not charged with murder but with concealing a body. He had moved to his father’s home in Texas after the death and was arrested this month when he returned for a brief visit to Fulton County, police said.

The three men are due in court next week for a bond hearing.

Salata, the defense lawyer,said the evidence wouldn’t support a murder charge.

“Very seldom do you see things charged like this and I don’t think it should be charged, ” he said. “It is a tragedy.”