As many as 50 refugees were found dead in a parked lorry in east Austria yesterday, and German Chancellor Angela Merkel said the discovery had shaken European leaders at a Balkans summit. Police made the discovery in the 7.5-ton lorry stopped, apparently since Wednesday, on the A4 motorway near the town of Parndorf, close to the Hungarian border, Hans Peter Doskozil, police chief of Burgenland, told reporters.He said he could not put an exact figure on the number of victims, whose bodies had begun to decompose."We can assume that it could be 20 people who died. It could also be 40, it could be 50 people," he said.Merkel told a news conference at the summit on the west Balkans in Vienna: "We are all shaken by the appalling news. This reminds us that we must tackle the issue of immigration in a European spirit - that means in a spirit of solidarity - and find solutions."Europe's largest economy has gone on the offensive in recent days to push for a joint EU response to the biggest migration crisis to hit the continent since World War 2 , as it prepares to host a record 800000 asylum-seekers this year."Never before have so many people fled political persecution and war as today. Many of them are seeking refuge here with us in Europe," Vice-Chancellor Sigmar Gabriel and Foreign Minister Frank-Walter Steinmeier said in the French daily Le Figaro.Tens of thousands of people, mainly from Africa and the Middle East, have put to sea this year in the hope of reaching Europe, often dangerously packed into small vessels never designed to cross the Mediterranean.Those who make it ashore have tried to make their way north via the Balkans, causing tension among countries along the route.Hungary plans to reinforce its southern border with helicopters, mounted police and dogs, and is also considering using the army as record numbers of migrants crossed razor-wire into Europe.Investigations were under way in Austria and Hungary after the bodies were discovered. The truck had Hungarian number plates, a Hungarian official said.Austrian Interior Minister Johanna Mikl-Leitner called it "a dark day" and underscored Vienna's demand that the EU adopt a way to distribute a wave of refugees fairly so that they would not have to turn to human traffickers."This is a signal on the European level to act as quickly as possible here," she told the news conference, adding that controls on international trains and border areas had been stepped up...