The Austrian government has released statistics showing that in 2017, four out of every ten migrants who claimed to be underage were lying in order to have a better chance of getting asylum.

The statistics come after medical tests showed that 347 migrants out of 867 who were flagged as potentially being adults, were found to be at least 18 or older, Kronen Zeitung reports.

The asylum seekers in questions were subjected to medical examinations including X-ray and physical, dental, and radiological tests which cost the Austrian taxpayer 1.2 million euros. The results follow similar tests done in 2015 and in 2016 where nearly a thousand migrants were found to be lying about their real age.

“Underage” migrants have also been involved with several high-profile crimes in both Austria and neighbouring Germany where some cities, such as Hamburg, have found that up to half of the underage asylum seekers are over the age of 18.

Nearly 1,000 ‘Child’ Migrants Caught Lying About Age https://t.co/MnEnXmbX9r pic.twitter.com/8eJQHNEKpq — Breitbart London (@BreitbartLondon) November 9, 2016

The most well-known case of a migrant claiming to be underage and going on to murder a young woman was that of Hussein Khavari, the rapist and killer of German student Maria Ladenburger. Tests found that he was an adult, while his own father claimed that Khavari could be as old as 33.

Earlier this month, another young girl, 16-year-old Manuela K., was found dead in the town of Wiener Neustadt, discovered under a pile of leaves by her own mother. Syrian migrant Yazan A., who claims to be 19 years old, was arrested shortly after the discovery of the young girl’s body and later admitted to the murder.

Earlier this week, Austrian authorities announced they would be conducting exams to determine whether Yazan A. was indeed the age he has claimed which could see his potential sentence in the case go from a maximum of 15 years in prison to a maximum life sentence if he is found to be over the age of 21.