An Afghan man who claimed he was 17 years old to be granted asylum in Germany where he later raped and killed an EU official's daughter is 33 years old, a court heard.

Hussein Khavari ambushed 19-year-old medical student Maria Ladenburger in Freiberg in October last year before raping her and drowning her in a river.

Khavari had applied for asylum as an 'unaccompanied minor' when the attack took place, but his father has told German authorities that he is much older.

On trial: Afghan migrant Hussein Khavari claimed he was 17 to be granted asylum in Germany, but his father says he is 33.

Charged: Hussein Khavari has admitted to raping and murderiong 19-year-old medical student Maria Ladenburger in Freiberg, Germany last year

Last month, dental checks found with 'near certainty' that Khavari is aged between 22 and 29 years old.

But his father, who lives in Iran, informed the court via telephone that his son is born in January 1984, making him nearly 34 years old, Welt reports.

This comes after an analysis of his canine tooth by research scientist Ursula Wittwer-Backofen, presented to the court last month, found him to be nearly ten years older than his claim of 17.

The upper right canine tooth had been removed eight months before Khavari attacked the teenager.

Khavari had kept the tooth as some sort of souvenir and it was later seized by police in Freiburg, southern Germany, where he has been standing trial for the past three months for the crime.

Police stand in front of the court in Freiburg ahead of a case that fueled a nationwide debate about the country's migration policy

Mrs. Wittwer-Backofen said it has been established with 99.7 per cent probability that his true age is between 22.05 and 29.55 years, but that she was certain he was 25.

This means when he is sentenced for Maria's murder he can expert no leniency for his age but a mandatory life sentence.

He had earlier testified that on the night of the killing he was so drunk he was ejected from a bar and left alone by his friends in town.

He claims he accidentally came across Maria who shouted out as she fell from her bicycle.

He said he pressed her mouth shut then choked her with a scarf and put her unconscious into the water.

Khavari's trial is taking place in Freiburg, where he was seen in handcuffs being led in to court (pictured)

'When I saw how pretty she was, I wanted to have sex with her,' he said, but claims he was too drunk.

He broke down in court and added: 'I want to apologize to the family of Maria'.

Reading from a statement he went on: 'I beg your pardon. I want to apologise to the family of Maria. I wish I could undo it. What I have done, I am sad for from the bottom of my heart '.

Prosecutors dispute his account of the murder and say he planned it beforehand.

Khavari ended a life rich in potential and polarised a nation struggling to adapt to over a million refugees in its midst.

It was learned after his arrest that he had been arrested and sentenced to ten years for attempted murder in Corfu in 2013 before coming to Germany seeking refuge in 2015 as an 'unaccompanied minor.'

The defendant Hussein Khavari is brought back into the court room wearing shackles after a break during his trial in Freiburg

German authorities knew nothing of his past and so let him into the country as a registered asylum seeker.

His victim, whose father is a senior legal adviser to the European Commission in Brussels, worked in her spare time in Freiburg helping out migrants in various shelters and homes.

The killing sparked frenzied new waves of hatred and fear of refugees. Even the leader of the country's police union said her death would have been prevented had the open door asylum-seeker policy of Chancellor Angela Merkel been less lax than it is.

After several court hearings Khavari said he did not know his true age but that he was no older than 19 - again an age would would have seen him sentenced as a juvenile.

But the tooth evidence now means he faces sentencing next year as an adult.