Schoolgirl Ana Kriegel's blood was found on a backpack, a pair of gloves, a mask and a set of knee pads which gardaí seized from the home of one of the boys accused of murdering her, a trial has heard.
The jury was also told the mask had a mixed DNA profile around the mouth and nose which contained all the elements of Ana's DNA and that of Boy A's DNA.
Earlier, the jury heard Boy A told a Garda interviewer he was "looking for horror movies online" when asked about a screenshot of a list of videos on his phone which included "15 most gruesome torture methods in history".
Gardaí also found a number of search items on Boy A's phone, one of which read "abandoned places in Lucan".
Two youths, Boy A and Boy B, who were aged 13 at the time, have pleaded not guilty before the Central Criminal Court to murdering Ana Kriegel (14) at Glenwood House, Laraghcon, Clonee Road in Lucan, on May 14 last year.
Boy A has also denied a charge of aggravated sexual assault.
John Hoade, a blood pattern and DNA expert with Forensic Science Ireland, was recalled to give evidence yesterday afternoon.
Just before lunch yesterday, gardaí gave evidence of obtaining a warrant and searching Boy A's home on May 24, 2018.
During the search, the court heard gardaí seized 59 exhibits, including a backpack which was found in Boy A's wardrobe.
In his evidence, Mr Hoade said he examined the backpack and its contents for blood staining on June 11, 2018.
He said the backpack contained a mask, a pair of black woollen gloves, black plastic knee pads, black plastic shin pads, and a black woollen snood.
He said there was blood staining on both the inside and outside of the backpack, and the DNA matched Ana Kriegel's DNA.
Mr Hoade said there was blood staining on the mask and it too matched Ana's DNA.
He further examined the area around the nose and mouth of the mask for any DNA, and said the mixed profile DNA sample matched that of Ana and Boy A.
Ana's DNA was also found on blood on the knee pads and gloves.
On Wednesday, Mr Hoade gave evidence he had not tested a blood-stained concrete block found at the crime scene. Yesterday, he said he had gone back and examined that concrete block, and the DNA from the blood matched Ana's DNA.
Dr Charlotte Murphy, also from Forensic Science Ireland, looked for male-specific DNA on a neck swab taken from Ana Kriegel.
Dr Murphy said this male-specific DNA matched Boy A's DNA profile. The possibility of this DNA being from someone unrelated to Boy A was one in 7,160, she said.
Cross examined by Patrick Gageby SC, Dr Murphy agreed it was possible this DNA transfer was caused by "casual intimacy".
Earlier, prosecution counsel Gerardine Small BL continued to lead Detective Garda Tomas Doyle through a series of interviews with Boy A.
During the fourth interview which began after 9pm on May 24, 2018, Gda Doyle showed a series of photographs of the room where Ana's body was found to Boy A.
When Gda Doyle pointed out blood in a photo, Boy A responded: "Oh, that's blood, my God."
Gda Doyle pointed out a wooden stick in a photograph, telling Boy A it was believed some of Ana's injuries were caused by it.
Boy A replied: "Oh my God."
The court heard interview four finished after Boy A's solicitor Donough Molloy said his client was "very distressed", was only 13 and had been in the Garda station since 8am.
The fifth interview began at 11.37am on May 25, 2018. Boy A was told gardaí had examined his mobile phone and had retrieved data from a Safari search engine.
Boy A told Gda Doyle: "That's not possible as I don't have Safari on my phone."
Gda Doyle said the phone had been examined by an expert.
"I don't have Safari on my phone so I don't know how," Boy A responded.
Gda Doyle told the court an exhibit was shown to Boy A during the interview. It was a screenshot of a list of videos saved on February 14, 2018 and included the "15 most gruesome torture methods in history" as well as "horror movies that will blow everyone away" and "10 top sexiest video game characters of 2017".
When asked what he was doing, Boy A said he was "looking for horror movies online".
This was an interest of his, he told Gda Doyle.
Boy A clarified that he was interested in ghost horror movies, but said he could not remember the last one he had watched. Asked what he typed into the search engine on February 14, 2018, Boy A said: "Horror movies."
A second printout was shown to Boy A during interview five. This data was also retrieved from Boy A's phone and part of it read "abandoned places in Lucan".
Asked if he remembered this, Boy A told gardaí: "If it was something I looked up regularly it would come up recommended."
During the sixth interview, sections of Boy B's interviews were put to Boy A. Asked if he had any clarification he wanted to make, Boy A said: "[Boy B] is lying, that's it."
The trial continues.