Berlin (AFP) - German authorities do not know the whereabouts of 130,000 asylum seekers, the government said in a parliamentary document seen by AFP on Friday.

Out of some 1.1 million asylum seekers registered in 2015, "about 13 percent did not turn up at the reception centres to which they had been directed," the government said in a written reply to a question from a lawmaker of the Left Party.

Some may have returned to their home countries, travelled on to another country, or gone underground, it said, adding that there may also have been repeated registrations of the same individual.

A spokesman for the interior ministry said a package of new measures approved by parliament on Thursday is expected to help address the problem.

These include plans for an identity document to be issued upon the arrival of a migrant, which would allow authorities to store personal data under a common database and thereby help to avoid repeated registrations.

The new rules, which includes restricting family reunions for some migrants, also lower the hurdles for the expulsion of convicted foreigners -- a key measure proposed after the New Year's rampage in Cologne, where hundreds of women reported being sexually assaulted and robbed in a crowd of mostly migrant men.