German Chancellor Angela Merkel stood firm Monday on her refugee policy, despite a drubbing in regional elections described as a "debacle" in which disgruntled voters turned to the anti-migrant AfD.

Merkel's Christian Democratic Union (CDU) was at the receiving end of voter anger, suffering defeats in two out of three states in Sunday's elections -- including in traditional stronghold Baden-Wuerttemberg.

The German and Greek leaders blasted Balkan countries for shutting their borders to migrants ahead of an EU ministers meeting Thursday, with Greek Premier Alexis Tsipras warning that the EU "has no future if it goes on like that".

Germany's Chancellor Angela Merkel said the closures are "neither sustainable nor lasting" in tackling Europe's biggest migrant crisis since World War II and would leave Greece bearing the burden of the influx.

Germany's right-wing populist AfD party made strong gains in local polls in western states on the back of rising support for its anti-migrant rhetoric, ahead of weekend key state elections.

The Alternative for Germany (AfD) became the third biggest party, with support reaching 13.2 percent, in Hesse state, according to initial results released on Monday.

German police on Thursday arrested a doctor suspected of having recruited a man of limited mental capacity to fight for the Islamic State organization in Iraq.

Investigators accused the 33-year-old German doctor of brainwashing the 24-year-old man with jihadist videos and later paying for his one-way ticket to Syria and Iraq.

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 centers to which they had been directed," the government said in a written reply to a question from a lawmaker of the Left Party.

The German parliament on Thursday approved new measures to tighten asylum rules in an effort to stem an unprecedented influx of migrants.

The package, which includes measures such as restricting family reunions for some migrants, was approved with a large majority of 429 votes to 147 against.

Facing rows of migrants in a German refugee center, Bavaria's justice minister delivers a civic values class and fires off questions at people from the Middle East, Central Asia and Africa.

"Who in this room knows people of the Jewish faith?" Winfried Bausback asks his audience in the makeshift classroom.

A group of 135 Afghan migrants landed back in Kabul from Germany on Wednesday after volunteering to return home due to a lack of prospects in Europe, officials said.

The International Organization for Migration arranged the transport and reception of the group, which included 107 males and 18 females including ten children.

German courts Wednesday tried three North African men for crimes committed on New Year's Eve in Cologne when hundreds of women reported being sexually assaulted or robbed.

But the city's police chief conceded that most perpetrators may never be caught over the spate of groping and other attacks that inflamed public debate about a huge influx of refugees and migrants.

Denmark's immigration ministry said Tuesday it had extended random identification checks along its border with Germany until March 4 in a move aimed at discouraging the arrival of more migrants.

"A large number of refugees and migrants are still trying to reach Europe and many among them are heading to Denmark and other countries in northern Europe," the ministry said in a statement.