UPDATED: May 12, 2011, 7:30 p.m.

WAUKEGAN, Ill. (WBBM/CBS) — The sister- and brother-in-law of a Round Lake Park woman, who overdosed April 15 and was the subject of a 10-day search, were charged

Thursday in connection with her death and the concealment of her body.

LISTEN: Newsradio 780’s Bob Roberts reports

The Waukegan couple, 33-year-old Sherry Best and her 37-year-old husband Charles were arrested pursuant to a warrant carrying a $1 million bond, said Round Lake Park Police Chief George Filenko.

Citing newly-completed toxicology tests and information the two have provided, Filenko says 34-year-old Melissa Best injected herself in the arm with heroin and died almost immediately in the efficiency apartment Sherry and Charles Best rented at the Crosslands Motel, on Illinois 41, in Waukegan.

melissa best Two Relatives Charged In Round Lake Park Moms Death

Missing Round Lake woman Melissa Best

But instead of making an immediate call to 911 to seek assistance, Sherry Best did nothing initially, Filenko said, eliminating any chance that her sister could be revived.

“Ten to 15 minutes is not too late,” Filenko said, drawing upon experience in other drug overdose cases.  “There are drugs, ‘anti’ drugs, that can be injected almost immediately and literally bring someone back from the dead.”

Instead, the first to try to render assistance to Melissa Best was her brother-in-law, who tried CPR unsuccessfully when he arrived at the apartment 20 minutes to 30 minutes later.

By that time, Filenko said, it was too late.

Filenko said that Sherry Best also admitted to using heroin that day.

Charles and Sherry Best soon decided to move the body and make it appear that she died elsewhere, Filenko said, for two reasons.  He said Charles Best was on parole and feared he would be found in violation and jailed. And Filenko said the couple’s two children were already in DCFS custody and they feared that they would lose custody permanently.

Filenko said Charles Best was the first to admit to moving the body. 

He allegedly told police that together, he and his wife carried Melissa’s body to her van and hid it in the back.

Charles Best allegedly said that he then drove the van to a Grayslake parking lot, where it was discovered 10 days later.

Melissa Best was reported missing on April 16 by her husband Clinton, who issued a statement through the police department.

“At no time did I ever see any signs or evidence that Melissa had any kind of addiction to any kinds of drugs,” he said, although he added she would occasionally abuse alcohol.

Filenko said Clinton and Charles Best worked side-by-side at a Waukegan business and said he found it especially appalling that Charles Best said nothing to his brother about Melissa’s death while the search continued.

Once the body was found, Filenko said police concluded “in a day or two” what had probably happened, but did not immediately tell Clinton Best, hoping Charles or Sherry would come forward.

“(Clinton) was extremely upset. He was distraught,” Filenko said, when police told him what had happened.  “He was very devastated.”

Clinton Best urged no mercy for his brother and sister-in-law. 

“To allow someone to die, and then hide them to the point where they cannot be found for 10 days, causing us to have worry about what has happened to them, shows just how heartless and cowardly these people are,” he said in the statement.

Sherry Best is charged with causing a drug-induced homicide, because she supplied the drugs; if convicted, she could face 15 to 30 years in prison. 

Both Sherry and Charles Best are charged with concealment.

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