BUDAPEST (Reuters) - Tens of thousands of Hungarians joined a protest march on Sunday against anti-Semitism, three weeks after the far-right Jobbik party won nearly a quarter of votes cast in a national election.

Budapest's annual 'March of the Living' has drawn an increasing number of participants in recent years to commemorate the deaths of around half a million Hungarian Jews during the Holocaust in World War Two.

The marchers, many holding European Union and Israeli flags, attended the inauguration of a Holocaust monument on a bank of the Danube where Jews were executed during the war. They then marched in silence through the city to an old railway station from which trains departed 70 years ago for Nazi death camps.

More people are taking part because they fear anti-Semitism is again on the rise, said Miklos Deutsch, 64, a restaurant manager, after a shofar, a traditional Jewish instrument made from a ram's horn, gave the signal for the march to start.

"The cause, indeed, is poverty. When the economy does not really work and people are poor, somebody has to be blamed, and the Jews and the gypsies are blamed," he said.

"The strengthening of Jobbik is dangerous," added Deutsch, whose parents lost most of their relatives in the Holocaust. Unemployment has fallen under the rule of Prime Minister Viktor Orban's conservative Fidesz party, which again secured a two-thirds parliamentary majority in this month's election.

But many Hungarians still struggle to make ends meet and this discontent has helped Jobbik increase its support to 21 percent of the national vote from 16 percent four years ago.

Jobbik denies being anti-Semitic but does little to dispel its reputation for intolerance. Its followers are often openly hostile to Jews and other ethnic and religious minorities.

"Anti-Semitism has risen. You can feel that in all segments of society: in politics, in media, in schools and in social intercourse," said another marcher, Gyorgy Burjan, a retired engineer, adding that Jobbik had capitalized on that.

Jewish groups have also protested against a plan to build a memorial to Hungary's 1944 German occupation, saying it would conceal the responsibility of local authorities who collaborated with the Germans to ship hundreds of thousands to the camps.

After Sunday's march, around 600 participants boarded a train bound for Poland, where they were due to take part in a commemoration at the Nazi death camp of Auschwitz near Krakow.