Ana Kriegel's murder trial has heard one of two boys accused of murdering her told a Garda he thought she had beaten the other boy up.

It is the prosecution's case that he lured the Kildare schoolgirl from her home in Leixlip and that the other boy sexually assaulted and murdered her.

Detective Garda Gabrielle Newton told the court she was assigned the role of investigating an alleged assault on Boy A.

He claimed he was attacked by two older boys in the park where Ana Kriegel was last seen alive on May 14th last year.

The prosecution claims his story is made-up, and that the injuries he sustained that day were the result of a struggle with Ana.

Detective Newton said a DNA sample was taken from Boy A as part of the investigation into the alleged assault in the park and without being asked, she said he made a comment that Ana had touched him in the chest area.

She said she spoke to Boy B a few hours after Ana's body was found three days after she went missing.

He told her he went to her house because Boy A wanted to meet her in the park to tell her he was not interested in her.

During a walk-through in the park, Detective Newton said he told her Ana was wearing a slutty top that day - and he thought she may have beaten Boy A up.

Reporting by Frank Greaney