SPIELFELD, Austria/BRUSSELS: On the Austrian-Slovenia border, one of the last stops on the migrant route to Germany, a policeman explains that after his 12-hour shift taking new arrivals' fingerprints, most are lost minutes after they are taken.

"We are not allowed to save the fingerprints," the Austrian policeman, who wanted to remain anonymous, said as he sat in a tent at the Spielfeld border crossing. "We do what we're asked to do."

Austria, which saw 700,000 migrants crossing its borders last year, says it is not legally allowed to save and share with other European states more than 90 percent of the fingerprint data it takes of migrants fleeing war and poverty, a potential security problem at a major migrant hub.

It is only required to upload onto Europe's shared fingerprint database, Eurodac, the data of those who actually apply for asylum in the country, which is less than 10 percent of those crossing into Austria.

So Austria takes digital fingerprints of everyone entering the country, checks whether they have a criminal record, but does not save the data if they want to move on to Germany, which most do.

Roz, a 28-year old Syrian mother of two, is surprised to hear that her family's fingerprints are neither saved nor shared.

"They need to know who we are. If you record fingerprints of refugees, it guarantees security in this country," she said as she was shown by Austrian officials onto a bus that would take her to the German border, her chosen destination.

Anachronism

The situation highlights how European laws are far behind the challenges of the continent's latest crisis, one that has already seen hundreds of thousands of migrants and refugees, mainly from Syria, flooding into the continent seeking a new life.

"That is a major problem, we have no records on these people, there are so many moving around the bloc and we have no trace of them whatsoever," said one diplomat in Brussels, adding that some EU countries have tried to push for changes but they were blocked due to privacy protection concerns.

Berndt Koerner, deputy executive director of Europe's border agency Frontex, said he was confronted with an "anachronism" in the sharing of migrant data.

"We are currently confronted with the problem that we cannot access certain databases, which can be used nationally in border controls," Koerner told reporters this month.

The system was not changed even after the evident security problems in tracing the movements of the surviving Islamist militants involved in the Paris attacks last November.

Only states on the EU's external borders, such as Greece and Italy, must save and share all fingerprint data.

Still, at a West Balkans summit in October all participants, including Austria, committed to registering, fingerprinting and uploading onto Eurodac all migrant data even on borders in the no-visa and border-control free Schengen zone.

Croatia and Finland, for example, save fingerprints of all migrants who arrive there, while Germany only lets in migrants who state they want to apply for asylum there.

Austria's coalition of the social-democrat SPO and Christian-conservative OVP has come under pressure in opinion polls from their right-wing, anti-Islam Freedom Party rivals since the latest migrant wave arrived last autumn.

Drawing ire from Brussels and accusations it was breaking EU law, Vienna this month introduced daily caps on how many entries it allows across its southern borders and the number of asylum requests it will accept.

But even as the coalition seems to attempt to coax back voters worried about migration, the two parties publicly blame one another for failing to create the legal grounds to save the fingerprints as talks began on how to amend the border law.