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A Georgia man whose toddler son died after he was left in a hot car for seven hours has been charged with murder in a case that has drawn widespread attention amid prosecutors' claims that he intentionally left the boy alone.

A Cobb County grand jury on Thursday indicted Justin Ross Harris on multiple charges including malice murder, felony murder and cruelty to children. The malice murder charge indicates that prosecutors intend to prove Harris intentionally left his son, Cooper, in the hot car to die.

The eight-count indictment also includes charges related to sexually explicit exchanges prosecutors say Harris had with an underage girl.

The case has attracted enormous national attention from the moment police arrested Harris in a parking lot where he had parked and pulled his 22-month-old son out of his car seat. Harris has told police he was supposed to drive his son to day care the morning of June 18 but drove to work instead and didn't remember the child was in back until he was driving to a movie after work.

Police have said the toddler was left in the vehicle for about seven hours on a day when temperatures in the Atlanta area reached at least into the high 80s. The medical examiner's office has said the boy died of hyperthermia — essentially overheating — and has called his death a homicide.

During a three-hour bond and probable cause hearing in July, the courtroom was packed with reporters, Harris' friends and family and people with no connection who were simply curious about the case. Among the evidence presented by a police detective: Harris was exchanging nude photos and racy messages online with several women as his son languished in the hot SUV; he had looked at websites promoting a child-free lifestyle; and he showed little emotion when questioned about his son's death.

Defense attorney Maddox Kilgore argued at the hearing that the evidence was insufficient and that the boy's death was a tragic accident.

"It was always an accident and when the time comes and we work through the state's maze of theories at trial, it's still going to be a terrible, gut-wrenching accident," Kilgore told a news conference Thursday afternoon. He added that his client is "a very broken guy" and was devastated after losing his son, livelihood and freedom.

Reached by telephone later Thursday, grand juror Vivien Sanders, 68, of Austell, said while jurors had several questions about the charges, "they were satisfied enough to where we made a unanimous decision." Sanders declined to comment further, citing the upcoming trial.

Harris will be arraigned in the next few weeks, and Cobb County District Attorney Vic Reynolds said he will decide before then whether to seek the death penalty.

The publicity could present difficulties when the case eventually goes to trial, said David Weinstein, a defense lawyer and former federal prosecutor in Miami who's not connected to the case.

"It presents an incredible challenge, certainly more so on the defense side than on the prosecution side because I don't think you're going to find anyone who looks favorably on Justin Harris based on what we know about him so far," Weinstein said.

The case also has key elements that heighten public interest, he said.

"We love our children and we love animals, and those are two things that really tug at the heartstrings of people," Weinstein said. "And here we have a poor innocent child who knows no better about anything, and if you believe the evidence, this is a guy who was looking to get rid of his kid and make it look like an accident."

Harris has been in jail since the day his son died.

"Today was another step in a long process," the district attorney said. "We look forward to the case running its course and, ultimately, justice being served in this matter."

The investigation continues, Reynolds said.

"The evidence in the case has led us to this point," he said. "Whether or not it leads us to anyone else remains to be answered."

Prosecutors have questioned Harris' wife, Leanna, and she has hired a criminal defense attorney, but no charges have been filed against her.

"I am surprised that the District Attorney is still contemplating after almost three months of reviewing the evidence whether or not to charge my client, if that is who he was referring to in his press conference," her attorney Lawrence Zimmerman said in an emailed statement. "By now, I would think they would have been able to make a final decision and clear her from any wrongdoing."

Atlanta defense attorney Page Pate, who's not involved in the Harris case, said the malice murder charge means prosecutors likely have more convincing evidence than they presented during the July hearing.

"There were a lot of suggestions about malice murder but no smoking gun," he said.

The indictment also accuses Harris of asking a girl under the age of 18 to send him a nude photo and of sending nude photos of himself and sexually explicit messages to her. It charges him with attempting to sexually exploit a child and with disseminating harmful material to a minor.

Prosecutors likely threw those charges in because they want to be able to bring up that evidence at trial, and a judge could rule they are inadmissible without the related charges, Pate said. The defense will likely try to have those charges isolated in a separate trial, he said.

Harris is a native of Tuscaloosa, Alabama, and moved to Georgia in 2012 to work for Home Depot.