In forgotten tapes from his civil lawsuit, OJ Simpson admitted to "hurting" his ex-wife Nicole Brown before her death. The footage shows the former American football star confessing to putting his hands on her neck, as he was questioned ahead of his civil trial in 1996.

Simpson, now 68, told his interrogator that he took "full responsibility" for "hurting" his wife, but denied killing her. At one point in the grainy video, Simpson looks stunned with his eyes widening with surprise as he was presented with a new piece of evidence. At other times, he rolls his eyes dismissively to the questions.

The tapes, which were only seen by lawyers working on the case, have now been released as part of a documentary called OJ Speaks: The Hidden Tapes, shown by ABC News. Simpson was acquitted in a criminal trial in 1995 of murdering Brown and her friend Ron Goldman. In the later civil case, brought by the victim's families, Simpson was found liable for the two deaths and ordered to pay $33.5m in damages.

Goldman family lawyer Daniel Petrocelli asked Simpson about his history with his ex-wife and showed him police photographs of her with a bruised face from before she died. He denies that he was responsible, saying: "It reflects doing a movie that we're doing and we're doing make-up."

However, Simpson allegedly admitted under questioning "I hurt my wife, yes" before being asked if he ever made her "black and blue". He responds by saying: "I think any marks that are on her, I take full responsibility for. I don't know what else you want to do. I take total responsibility."

Later he is asked by the lawyer if he has ever had his fingers around her throat. Simpson reportedly replied: "I could have touched her neck, yes."

During the questioning, Simpson was also asked about the men's size 12 Bruno Magli brand shoe print stamped in the victims' blood that was found at the scene of the murder in Brentwood, Los Angeles. He denied they were his and claimed they were "ugly ass shoes" that he would never wear.

However, Simpson is later confronted with a newspaper article with a picture of him wearing a pair of the same brand of shoe nine months before the murder. Simpson is stunned with his eyes widening and mouth agape. Asked if it was him, Simpson admits: "It appears to be me, yes."

Simpson is currently serving a jail sentence of up to 33 years for armed robbery for attempting to steal sports memorabilia he claimed was his in Las Vegas. He has failed to pay the Goldman family any of the $33.5m he owes in damages.