By Holly Yan and Nick Valencia
ATLANTA (CNN) -- A series of search warrants released Monday could reveal more clues about what happened the day a Georgia toddler died in a sweltering car -- and whether his father abandoned him on purpose.
The 16 search warrants in the case against Justin Ross Harris seek the medical records of Harris and his late son, Cooper Harris; a DVD; a 2-gigabyte memory card; a 32GB thumb drive; and an external hard drive.
While Harris remains in jail charged with murder, a slew of recent claims have intensified the case.
Among the most shocking allegations: Harris messaged six women and exchanged explicit texts from work while his 22-month-old was dying, a Cobb County detective testified at a hearing Thursday.
Harris' attorney repeatedly objected to Detective Phil Stoddard's testimony claiming that Harris sexted the women -- one of whom was underage at the time. But the judge allowed the testimony.
Police say Harris, 33, left his toddler, Cooper, strapped into a car seat under a baking sun for seven hours while he went to work on June 18. Records show that the mercury topped 92 that day, and police say the temperature was 88 degrees when the boy was pronounced dead in a parking lot not far from his father's workplace.
Cobb County Chief Magistrate Frank Cox found probable cause to move forward on murder and child cruelty charges.
"For him to enter the car ... when the child had been dead and rigor mortis had set in, and the testimony is the stench in the car was overwhelming at that point in time, that he -- in spite of that -- got in the car and drove it for some distance before he took any action to check on the welfare of his child, I find there is probable cause for the two charges contained in the warrant," Cox told a packed courtroom.
The judge denied bail for Harris, who has pleaded not guilty.
In addition to the charges he faces in connection with his son's death, Harris may also be charged with felony sexual exploitation of a minor and misdemeanor illegal contact with a minor, Stoddard said. Harris allegedly sent explicit photos, including one of an erect penis, to an underage female.
The detective also testified about Internet searches that could raise eyebrows given the context of the case.
Before his son's death, Harris had visited a Reddit page called "child-free" and read four articles, Stoddard said. He also allegedly searched how to survive in prison.
Among the other details police have released is that Harris and his wife, Leanna Harris, told them they looked up how hot a car needed to be to kill a child.
Five days before Cooper died, Ross Harris twice viewed a sort of homemade public service announcement in which a veterinarian demonstrates on video the dangers of leaving someone or something inside a hot car.
Leanna Harris told police that she had recently seen a story on a state initiative aimed at reminding people not to leave children in cars and that it was a fear of hers, Stoddard said.
Ross Harris "stated that he recently researched, through the Internet, child deaths inside vehicles and what temperature it needs to be for that to occur," police have said, adding that Harris told investigators "he was fearful that this could happen."
During questioning, Leanna Harris "made similar statements regarding researching in car deaths and how it occurs," according to police.
The time frame for the alleged research remains unclear.
'I felt his pain; I even wept'
Thursday's probable cause hearing was expected to last 90 minutes; it stretched for some three hours.
A good chunk of that time was spent discussing how Ross Harris acted after he pulled into a shopping center asking for assistance with his son.
Witnesses told police they heard "squealing tires, and the vehicle came to a stop," Stoddard testified. Harris got out of the car yelling, "Oh, my God, what have I done?" Stoddard said.
Harris then stood there with a blank look on his face, the detective said. When a witness told Harris his son needed CPR, Harris went to the other side of his vehicle and made a phone call, apparently to tell someone his son was dead, a witness told police, according to Stoddard.
Harris never called 911, and when an officer told him to get off his phone, he refused and even said, "F*** you" before an officer took his phone and handcuffed him, the detective said.
He also said that Harris told police he couldn't reach anyone on his telephone, but phone records show that Harris made three calls after he discovered his son's body -- including one with his employer that lasted six minutes, Stoddard said.
But witness Leonard Madden offered a different version of what happened. Madden and an acquaintance were leaving a restaurant when they noticed a commotion and approached within 3 or 4 feet of a clearly distraught Harris.
"He was crying. He was hollering," Madden testified, recounting the father saying, "Oh, my God! Oh, my God, my son is dead!"
"I felt his pain; I even wept," Madden said.
According to Stoddard, Harris made statements that police felt were strange, including "I can't believe this is happening to me" and "I'll be charged with a felony."
"It was all about him," Stoddard said. "'Why am I being punished for this?' It continued. It was all very one-sided."
The detective said Harris talked about losing his job. He testified that messages between the Harrises indicate the two were having financial problems.
Ross Harris had recently been passed over for a promotion, and the couple had two insurance policies on Cooper, one for $2,000 and one for $25,000, the detective said.
At another point in the interview room, Stoddard said, Leanna Harris asked her husband about what he had said to police.
"She asked him -- she had him sit down, and he starts going through this. And she looks at him, and she's like, 'Well, did you say too much?' " the detective testified.
'Nothing was weird'
While prosecutors painted Ross Harris as a terrible, in fact criminal, father, the defense called witnesses who testified on his behalf.
James Alex Hall, who worked with Ross Harris and had run a Web development company with him for the past two or three months, said Harris didn't act out of the ordinary on the day his son died.
"I would say normal as you could be. Nothing stuck out. Nothing was weird," Hall said.
CNN's Eliott C. McLaughlin, Dana Ford, Natisha Lance, Devon Sayers, Faith Karimi and Marlena Baldacci contributed to this report.
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