BERLIN (Reuters) - Thousands of former Taliban fighters may have entered Germany over the past two years among an influx of more than a million migrants and refugees, Der Spiegel magazine reported on Saturday.

Germany’s Federal Office for Migration and Refugees (BAMF) informed security officials that thousands of migrants had identified themselves as former Taliban insurgents during the asylum application process, the magazine said.

It added that at least 70 Afghan men were being investigated by Germany’s over-stretched chief federal prosecutor, though it was not clear whether all of them were suspected of being active Taliban militants.

Six are being held in investigatory detention and preliminary court hearings involving several others are due to start next week, the magazine added.

No comment was immediately available from the migration office or federal prosecutors.

The government of Chancellor Angela Merkel, under fire for allowing in so many migrants, especially after several militant attacks linked to migrants last year, has been actively deporting groups of rejected Afghan asylum seekers.

Merkel, seeking a fourth term in a Sept. 24 election, this month defended the increase deportations of rejected Afghan asylum seekers, saying all other European Union countries were doing the same.

She said about 55 percent of Afghans were granted refugee status in Germany, while 45 percent were turned down.