BOSTON (CBS) — Testimony in the Bella Bond murder trial continued Wednesday, with an ex-girlfriend of the little girl’s accused killer taking the stand.

Michael McCarthy is being tried for first-degree murder in the death of two-year-old Bella in 2015.

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Michael McCarthy in court Wednesday during his murder trial (WBZ-TV)

McCarthy was living with the girl’s mother, Rachelle Bond, at the time of the murder. Prosecutors say he struck and killed Bella because he was obsessed with the occult and believed she was a “demon.” The defense, however, claims Rachelle Bond killed her daughter.

Taryn Devlin said she and McCarthy dated as teenagers, and moved to Oregon with him at one point.

She said that, as teens, they used to find out-of-the-way places to drink alcohol and use heroin–places like the area near the Black Falcon terminal, which is also where Rachelle Bond says McCarthy dumped Bella’s body.

Earlier Wednesday, the court heard testimony from a series of investigators and forensic experts.

Massachusetts State Police Trooper Anthony Alestock, who searched the apartment Bond and McCarthy shared as part of the investigation into Bella’s death, said he took demonology books from the apartment.

On cross-examination, he admitted the apartment was not secured between searches in September of 2015, because there was initially no plan for a second search.

“People could have gone in, taken things, left things in between those two searches, and the authorities would not have known about that?” asked defense attorney Jonathan Shapiro.

“That is a possibility,” Trooper Alestock answered.

State Police Crime Lab forensic scientist Jennifer Montgomery was up next, and told jurors she found hairs in the refrigerator at Bond and McCarthy’s apartment.

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“I was given information that someone with longer hair may have been inside the fridge, so I collected those,” she said.

Montgomery said that the refrigerator was tested for blood, and that none was found.

Rachelle Bond said in her testimony that McCarthy stored Bella’s body in the fridge after her death and before he tossed her body into Boston Harbor.

Bella’s body washed up on a Deer Island beach in July of 2015. On Tuesday, several forensics experts were called to the stand to testify about Bella’s murder and the path her body took to get to that beach.

Bella was known as Baby Doe as she went unidentified for months. Police said the digitally-generated photo of the toddler had been viewed on the internet more than 50 million times.

Rachelle Bond’s daughter Bella and the image of Baby Doe issued by police. (Facebook photo and State Police image)

State Police DNA scientist Elisse Coronado testified that the DNA profile of Baby Doe’s matched that recovered from three nasal aspirators that belonged to Bella that were found in Bond and McCarthy’s apartment.

She also said nobody else’s DNA was found on Bella’s body, or the blanket and bag she was found with.

The prosecution is expected to rest their case this week, and it is not yet clear whether or not McCarthy could take the stand in his own defense.

The judge said Tuesday that the case would likely be going to the jury for deliberation next week.

WBZ NewsRadio 1030’s Ben Parker reports

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