Updated

Some 20 German police officers have joined Serbian security forces on Serbia's border with Hungary to try to halt a torrent of migrants that has alarmed many European Union countries.

The Germans, equipped with vehicles with thermal vision cameras, were starting their patrols Friday.

In the last few months, tens of thousands of mostly Kosovo Albanians seeking a better life in the EU have flooded across Serbia into EU member Hungary. The migrants also have included many Syrians, Afghans, Iraqis and others.

Kosovo, which declared independence from Serbia in 2008, is one of the poorest countries in Europe.

Once migrants are inside Hungary, they can travel freely to most other EU countries. Many seek asylum in richer EU states such as Germany, France or Sweden.