Survivors of Tasmania’s Port Arthur massacre have attacked 60 Minutes for airing an interview with mass murderer Martin Bryant’s mother, Carleen.

In the interview, Carleen Bryant questioned the guilty verdict and said she believes that, if Martin’s father had not committed suicide, the 1996 Port Arthur massacre in Tasmania would not have happened.

On last night’s 60 Minutes, Carleen Bryant was asked what her dead husband, Maurice, would have thought of the Port Arthur murders her son was convicted of.

“Well I don’t believe it would have happened,” she answered.

Bryant became Australia’s worst mass murderer when he killed 35 people and wounded 20 others after opening fire in the Broad Arrow cafe in Port Arthur.

He is serving 35 life sentences in Risdon prison just outside Hobart.

However, Martin’s mother has questioned whether her son was really guilty of the murders.

She said that for weeks after the massacre Martin claimed that he was never in Port Arthur and she believed him and that there was no evidence against him.

“A lot of people on that day came forward after, people who had known Martin for years, that as far as they were concerned they didn’t recognise the gunman as Martin Bryant,” Carleen said.

However, survivors are angry that Carleen has re-opened old wounds.

Anne Francis, one of the few who managed to escape the gunman, said Carleen Bryant needed to let them all move on.

“I can understand that she could be distressed, but doesn’t she have the grace to shut up?” she said.

“When’s it going to stop?”

Martin Bryant, who was diagnosed with Asperger’s syndrome three years ago, was described by his mother as a difficult child with anger problems.

“Martin was different, I’ll put it that way,” Carleen said.