Austrian Chancellor Werner Faymann and German Vice Chancellor Sigmar Gabriel on Saturday called for United Nations countries to contribute an extra five billion euros ($5.65 billion) in aid for refugees living in camps in Lebanon and Jordan.

"We have to help countries where the misery is so great that people are going on the road," Gabriel said, in reference to the tens of thousands of migrants -- many of them Syrian refugees -- who have headed to Europe in recent months.

Thousands of migrants sought their way through a chaotic maze of rumor and proliferating border controls in the western Balkans on Saturday.

In the latest chapter in the EU's escalating refugee crisis, Croatia, Hungary and Slovenia tussled over how to cope with a wave of refugees desperate to reach northern Europe.

An Iraqi man with a jihadist background who stabbed a German policewoman before officers shot him dead in Berlin was presumed to have "acted alone", prosecutors said Friday.

Rafik Mohamad Yousef, 41 -- who had done jail time for a 2004 Berlin assassination plot against former Iraqi prime minister Iyad Allawi -- had a history of aggressive and unstable behavior, recently threatening a judge and other public officials.

Two German tourists were briefly detained in central Moscow after attempting to fly a drone over the Kremlin, a police spokesperson told AFP on Friday.

The tourists -- a father and his son -- were held by police after they launched a drone near one of the Kremlin's iconic towers. 

Germany on Friday criticized Hungary's border closures to migrants, saying they do "not contribute to a sustainable solution" to the refugee crisis.

Berlin "is aware of the great challenges" faced by transit countries including Greece, Macedonia, Serbia, Hungary and Croatia, said Chancellor Angela Merkel's spokesman Steffen Seibert.

German police on Thursday shot dead an Iraqi man who wounded a policewoman with a knife in Berlin, with prosecutors saying he was a "suspected Islamist."

The 41-year-old man had previously been sentenced in 2008 to a jail term for planning an attack against former Iraqi prime minister Iyad Allawi, a prosecution spokesman told AFP.

U.N. Secretary-General Ban Ki-moon has praised Lebanon, Jordan and Turkey for taking in millions of refugees from the war in Syria, which is now in its fifth year.

“Lebanon is hosting Syrian refugees equal in number to 25 per cent of its population,” Ban told a news conference on Wednesday less than 10 days before world leaders gather at the U.N. Headquarters in New York for general debate of the 70th session of the General Assembly.

Germany plans to expand its naval operations against human traffickers as part of an EU mission in the Mediterranean, Chancellor Angela Merkel's cabinet decided Wednesday.

"The government today decided on the participation of German armed forces in a new phase of the EU-led Operation EUNAVFOR MED," said Merkel's spokesman Georg Streiter.

Hundreds of migrants who had massed at the main train station in the Austrian city of Salzburg left on foot Wednesday in the hope of reaching Germany, a city spokesman said.

One day after Salzburg warned that the station might have to close due to the large numbers of migrants, government spokesman Johannes Greifeneder said the situation had "relaxed".

Several dozen migrants entered Croatia from Serbia early Wednesday, the first to enter the EU country after Hungary sealed its borders to thousand of people entering every day, an AFP correspondent saw.

The group of mostly Syrian or Afghan men, women and children crossed the border -- which was marked by nothing more than a stone -- early Wednesday morning and were picked up by police as they walked across a field.