Jozef Puska told his brother that he had unintentionally "cut" a woman and it was "probably bad" on the night he murdered Co Offaly teacher Ashling Murphy, a trial has heard.
The jury heard that Marek Puska also told gardaí he "logically inferred" that Jozef had "murdered that girl", but said Jozef had told him he did not intend to cut her.
Gardaí put it to Marek Puska that he asked his sister-in-law, Viera Gaziova, to burn Jozef Puska's clothes because he believed Jozef Puska might have been involved in Ms Murphy's murder.
Marek Puska replied: "Yes, but not in those words, exactly."
Marek Puska (36) is accused of withholding information that was crucial to the investigation into Ms Murphy's murder in January 2022.
He is on trial with his brother Lubomir Puska Jnr (35), who is also accused of withholding information.
Their wives, Jozefina Grundzova (31) and Ms Gaziova (38), are accused of impeding Jozef Puska's apprehension or prosecution by burning the clothes he wore when he murdered Ms Murphy.
Each accused, who have an address at Lynally Grove, Mucklagh, Tullamore, Co Offaly, has pleaded not guilty.
The trial previously heard that Jozef Puska has been convicted of murdering Ms Murphy, a 23-year-old schoolteacher who was exercising by the canal near Tullamore when Jozef Puska stabbed her repeatedly in the neck.
Sgt Lisa Shannon told prosecutor Anne-Marie Lawlor SC that she arrested Marek Puska on 26 January 2022, on suspicion of assisting his brother after Ms Murphy's murder.
In his first interview, Marek Puska said he wanted to tell the truth and described what he did on the day of the murder.
He said the family was concerned that Jozef Puska was missing all day, but then he arrived home looking like he had been beaten up. Marek Puska said there were three holes in Jozef Puska's abdomen and swelling on his head. He was shaking and unable to speak, he said.
He said Jozef Puska told him he had been sitting on a bench and stabbed himself. He said a woman started screaming and shouting, "Don't do that, stop harming yourself."
He said the woman tried to grab his arm and he, Jozef Puska, "might have had a knife in his hand, then he hit somebody".
Marek Puska recalled his brother saying that he "might have hurt that person" or that he "could have cut her".
When asked if Jozef Puska confessed to him, he said: "Yes, something had happened. He had tried to hurt himself and this woman came and he cut her."
He said Jozef Puska told him that he "struck out and cut her" and that it was "probably bad". Marek Puska added: "He said something about a dead woman but I didn't ask if dead or alive. You don't ask in a situation like this."
In a later account, Marek Puska said that the woman did not want Jozef Puska to stab himself and she grabbed him and tried to drag his hand away, saying "don't do that to yourself".
He said Jozef Puska wanted to take his own life and she stopped him. From his brother's account, Marek Puska said he thought it happened quickly and that his brother did not intend what happened.
Marek Puska said he told his wife, Ms Grundzova, that Jozef Puska had "murdered that girl" but he said Jozef had not been specific about what happened.
"He told me a situation from which I logically inferred," he said.
It is alleged that Marek Puska failed to disclose that Jozef Puska had returned home on the night of Ms Murphy's murder with visible injuries and admitted to killing or causing serious injury to a woman.
It is further alleged that he knew of the arrangement to burn Jozef Puska's clothes and that Jozef Puska travelled to Dublin later that night.
Lubomir Puska Jnr, it is alleged, also withheld that Jozef Puska returned home with visible injuries, admitted to "cutting a female", and travelled to Dublin.
Both men have pleaded not guilty to the offences, which are charged under the Offences Against the State, Amendment Act 1988.
Ms Grundzova, who is married to Marek Puska, and Viera Gaziova, who is married to Lubomir Puska Jnr, are accused of assisting in burning clothing between 12 and 14 January, without reasonable excuse, intending to impede the apprehension or prosecution of Jozef Puska, knowing or believing him to have committed the offence of murder or some other arrestable offence within the same category or of a similar nature.
Ms Grundzova and Ms Gaziova have pleaded not guilty to the offences, which are charged under the Criminal Law Act 1997.
The trial continues before Ms Justice Caroline Biggs and a jury of seven men and five women.
