Over 130,000 migrants missing in Germany

The interior ministry said the reasons could be traveling on to a different country or “submersion into illegality”.

Some asylum seekers who have family or friends already living in Germany might decide to stay with them, rather than in big reception facilities with little information or few things to do.

The head of Germany's federal office for migration Frank-Juergen Weise said on Thursday that there are currently up to 400,000 people in the country whose identities are unknown to authorities.

Germany is also struggling to send back asylum seekers to other EU countries under the Dublin regulation, which says people have to register their request in the country where they first enter the EU.

German authorities made a request to a European partner to take back refugees for only one in every 10 applicants. In 2014, this was the case for one in every five refugees.

The report comes on a day when the German upper house, the Bundesrat is to hold a final vote on new asylum rules.

The legislation, already passed by the Bundestag, the lower house on Thursday, aims to speed up asylum procedures, making it easier to deport migrants whose claim has been rejected.

It also sets up special reception centers in which asylum applications by certain groups of asylum-seekers would be processed within three weeks.

Asylum seekers from so-called “safe countries of origin”, where they can be sent back or people who have refused to help authorities process their applications would be housed there.

The bill was criticised for introducing a measure that makes asylum-seekers wait two years before they can have family members join them in Germany.

This will also affect minors wanting to be reunited with their parents.

Interior minister Thomas de Maiziere earlier defended the measure saying: "We do not want parents send to their children ahead of them, with the risk of them facing mortal danger," adding that the introduction of new regulations would also simplify the deportation of foreign criminals.

Die Linke criticised the measures as “illegal, un-Christian and immora"l.

Europol, the EU's police agency said earlier this month that about 10,000 migrant children who travelled to Europe are currently unaccounted for.

Last year Germany took in 1.1 million asylum-seekers.