A boy accused of murdering Ana Kriegel told gardai he saw his co-accused "flip" the schoolgirl and "start to choke her", a trial in Dublin has heard.
Two youths, aged 13 at the time and who cannot be identified, have pleaded not guilty to the murder of the 14-year-old in Lucan last May. Boy A has also denied aggravated sexual assault.
Boy B told gardai that he saw Ana lying on the floor of an abandoned house and Boy A "was on top of her, choking her"as he took off her clothes.
Boy B said he "sprinted" away when Boy A looked up and saw him standing in the doorway.
Ana had started to cry, Boy B said, and she kept saying "no, no, don't do it".
Yesterday,jurors at the Central Criminal Court continued to watch video footage of interviews gardai conducted with Boy B on May 25, 2018.
At the start of a fifth interview, which the jury heard on Wednesday, Boy B told gardai he heard Ana scream after she and Boy A went into the abandoned house.
He said he ran away because he was scared and he thought Ana and Boy A had been attacked.
Boy B said he didn't go into the house.
Jurors continued to hear the rest of interview five yesterday. In it, Detective Garda Donal Daly told Boy B he needed him to tell the truth.
During the interview, he said Boy A and Ana went into the house, and he started to follow them, but Boy A said "no, we'll be all right".
Asked if he went into the room with the carpet, where Ana's found was found, Boy B said he looked in but didn't go in.
Boy B said Boy A went into the room with Ana. He was about to leave when he saw Boy A put his arm around Ana and "kind of hugged her, I guess".
Boy B said Boy A put his arm around Ana and he "flipped" her and that's when he (Boy B) ran out of the room.
He said he saw Boy A "flip her and start to choke her".
He said Boy A started taking Ana's clothes off her. Boy B said Boy A looked up at the door where he (Boy B) was standing and he ran away.
"Boy A didn't follow me", he said, adding that's when he heard screaming.
Boy B said he saw Boy A take off Ana's jumper and then her T-shirt, but that he left before Boy A started taking off her bra.
"It looked horrifying," he said.
Gardai asked Boy B to tell him the exact position Ana was in.
"She was lying on the floor. (Boy A) was on top of her, choking her as he took off the clothes," he said.
The trial continues.