German police are investigating an explosion that damaged the car of a left-wing politician who had been working in support of refugees in Germany.

The incident comes amid increasing tensions across Germany following a growing influx of refugees from the conflicts in Syria and Iraq and also from the Balkans.

Pictures today showed more migrants arriving by boat on the Greek island of Lesbos and others trying to catch trains through the Balkan states to countries further inland.

Another 243 migrants have also been rescued by the Irish Navy in the Mediterranean.

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Migrants pull an overcrowded dinghy with Syrian and Afghan refugees arriving from the Turkish coasts to the Greek island of Lesbos

Nearly 50,000 people have illegally entered the country this year, mostly Syrian refugees who risk the sea crossing from Turkey in dangerous, overcrowded boats

From Greece, most migrants try to continue north through the Balkans to more affluent European countries such as Germany

The crew of the LE Niamh took the 183 men, 33 women and 27 children from a wooden barge about 80km (50 miles) north-west of the Libyan capital, Tripoli.

Weather conditions were said to be relatively calm during the three-hour operation this morning with all the migrants given food, water and medical attention on board.

The Irish Navy crew, the second to take part in the humanitarian mission in the Mediterranean, has rescued more than 1,000 migrants in the three weeks they have been at sea.

In Germany, the number of asylum applications in Germany is expected to at least double this year from around 200,000 in 2014.

Police said it wasn't clear what caused the blast that damaged the car of Michael Richter, a town councilor in the Dresden surburb of Freital, but that detectives were treating it as intentional.

A member of Die Linke, he is a supporter of refugees and the attack is seen as an escalation of the campaign by neo-Nazis' against them.

In the first half of 2015, Germany has seen almost as many far-right crimes against refugee accommodation as in all of 2014, according to the Interior Ministry.

Of the 173 crimes recorded, 19 were violent.

Migrants queue to buy tickets for a train heading to the Serbian border at the train station in Gevgelija, in the Former Yugoslav Republic of Macedonia. Greece and Italy are the main entry points for Europe-bound asylum seekers and economic migrants

Scrum: Migrants push to get onto a train heading to the Serbian border at the train station in Gevgelija

Migrants walk on the railway tracks at the train station in Gevgelija. Greece and Italy are the main entry points for Europe-bound asylum seekers and economic migrants. After they have reached the bloc, many start to make their way to wealthier countries in Western Europe

Incidents have been reported in recent weeks in several regions, primarily vandalism against new refugee homes being built.

In Freital, there were protest recently against a new asylum home and clashes with pro-refugee activists.

Antje Feiks, a senior official in the regional branch of the Left Party, suggested that the right-wing Pegida movement, which has staged regular rallies in Dresden, has stirred up more violent anti-immigrant sentiment in the area, even though its support has waned.

The rallies 'have fuelled a racist sentiment in which people are motivated and legitimised to use violence,' she said.

Migrants sleep in a park in Athens, where they found a temporary shelter after arriving from Greek islands

Greece received more boat arrivals than any other European country in the first half of 2015, with about 101,000 migrants arriving on Greek shores

Immigrants receive a meal offered by Caritas Greece on its premises in the centre of Athens

On Sunday, vandals broke half a dozen windows in a hotel in another part of Dresden that is being converted to house refugees starting this week and on Friday supporters of a far-right party clashed with backers of a new camp for refugees in the city.

The incidents prompted Rainer Wendt, the head of the German Police Union, to call for a ban on demonstrations within a kilometer of centers housing refugees.

'People who flee persecution have the right not to look into the faces of those throwing stones,' Wendt told the Saarbruecker Zeitung newspaper.

The Defense Ministry on Monday announced a plan for six former barracks vacated by the military to be been made available for refugee housing, and two further barracks still in use to be partly used for refugee housing.