Josef Fritzl, the Austrian engineer who kept his daughter as a sex slave in a secret cellar underneath the family home for 24 years, has been sentenced to life imprisonment, having been found guilty of a catalogue of crimes including the negligent murder of one of the seven children he fathered with his daughter.

The jury at St Pölten court found him guilty on all counts – of negligent murder, enslavement, incest, rape, coercion and false imprisonment. Fritzl quietly accepted the verdicts and waived his right to appeal.

It has not been decided exactly where the 73-year-old will serve his sentence, though he will initially be transferred to the psychiatric wing of a prison in the capital, Vienna, for assessment, the court authorities said.

The life sentence would entail a minimum of 15 years in prison, according to Franz Cutka, vice president of St Pölten courts. The 11 months he has already spent on remand count towards that sentence, he added.

After 15 years, he could apply to three judges for parole, but Fritzl's lawyer said his client expected to spend the rest of his life in prison.

The homicide count of "murder by neglect" was the most serious of the charges against him, and the jury gave him the maximum punishment allowed by law.

The jury was not swayed by Fritzl's 11th-hour confession of guilt, or his claim to be sorry "from the bottom of my heart".

In what was seen as a last-ditch attempt to mitigate his punishment, the 73-year-old defendant had made an emotional statement to court this morning.

"I regret from the bottom of my heart what I have done to my family. Unfortunately, I cannot make amends for it. I can only try to look for possibilities to try to limit the damage that's been done," he said.

But prosecutor Christiane Burkheiser urged the jury not show mercy just because he had pleaded guilty.

She told them: "Don't be duped like Elisabeth was 24 years ago."

At a press conference after the verdict, Erich Huber-Günsthofer, the deputy director of St Pölten prison, where Fritzl has been held since his arrest last April, said the prisoner would initially be sent for assessment at the Mittersteig prison in Vienna. At Mittersteig, there is a psychiatric wing where Fritzl's mental health will be assessed.

Huber-Günsthofer, said that five questions would be asked: "Can he have therapy? Is he willing to undergo therapy? Can he change his ways? Is he ready to change his ways? And how much of a risk does he pose to others?"

Fritzl may then be transferred to another prison or psychiatric institution of his choice. "He has the right to voice an opinion on where he should be sent, but this wish has to tally with any expert opinion and with the directorate of the prison," added Huber-Günsthofer

By giving Fritzl a life sentence, the jury ensured he received the maximum punishment for the crimes he committed over more than two decades.

Twenty-four years ago, he lured his then 18-year-old daughter into the cellar of their family home. There, in this damp, windowless prison, Fritzl raped her more than 3,000 times, his abuse resulting in seven children.

One of the babies, a twin boy called Michael, died from breathing difficulties shortly after being born in the cellar.

Fritzl failed to get the boy medical help and later burned his body in an incinerator. It was this failure that resulted in a guilty verdict for the most serious charge against him, that of murder through negligence, which carries a life sentence.

Adelheid Kastner, the forensic psychiatrist who spent 25 hours with Fritzl in order to produce a report on his mental health, told the court yesterday that he should be sent to a secure psychiatric facility.

Kastner told the jury that locking him up without therapy and treatment could be dangerous, and that there was a real risk he would try to take his own life.