At first glance, the shop on a nondescript street in this chaotic capital looks standard-issue military. Fatigues. Camouflage. Hunting gear. Deeper inside, the political message emerges. Black T-shirts emblazoned with modified swastikas — the symbol of the far-right Golden Dawn party — are on sale. A proudly displayed sticker carries a favorite party slogan: “Get the Stench out of Greece.”

By “stench,” the Golden Dawn — which won its first-ever seats in the Greek Parliament this spring and whose popularity has soared ever since — means immigrants, broadly defined as anyone not of Greek ancestry. In the country at the epicenter of Europe’s debt crisis, and where poverty and unemployment are spiking, the surplus shop doubles as one of the party’s dozens of new “help bureaus.” Hundreds of calls a day come in from desperate families seeking food, clothing and jobs, all of which the Golden Dawn is endeavoring to provide, with one major caveat: for Greeks only.

To fulfill its promise of a Greece for Greeks alone, the party appears willing to go to great lengths. Its supporters — in some instances with the alleged cooperation of police — stand accused of unleashing a rash of violence since the party rose to national office, including the stabbings and beatings of immigrants, ransacking an immigrant community center, smashing market stalls and breaking the windows of immigrant-owned shops.

Attacks have not stopped at foreigners. One Golden Dawn legislator slapped a left-wing female politician on national television. Party supporters have attempted to shut down performances of progressive theater. Activists see the party’s hand behind three recent beatings of gay men. The Golden Dawn has also begun engaging left-wing anarchy groups in street battles — more evidence, observers say, of a societal breakdown that some here fear could slide into a civil war if Greece is forced out of the euro and into an even deeper crisis.

But perhaps more worrisome, critics say, are signs that the Golden Dawn is establishing itself as an alternative authority in a country crippled by the harsh austerity imposed by its international lenders. It has set up its own “pure” blood bank, providing and accepting donations to and from Greeks only, in a nation of 11 million that is also home to roughly 1.5 million refugees and migrants, many of them from the Middle East, South Asia and Africa. As the party attempts to place a swelling number of unemployed in jobs, its officials say they have persuaded a major restaurant chain to begin replacing immigrants with Greek workers.

Landlords can seek the party’s help with the eviction of immigrant tenants. The Golden Dawn can provide not only government health inspectors and lawyers sympathetic to its goals, but also security, in the form of black­-uniformed followers with military haircuts who salute one another with upraised fists.

From his office inside the shop, Elias Panagiotaros, one of the new national legislators from the Golden Dawn, denied that the party is engaging in systematic attacks. But ethnic Greeks, he added, “have the right to protect themselves and their property from all these illegal savages.”

“During difficult periods of war or economic disaster, as we are facing now, there are people who have to do the hard job, the dirty job,” Panagiotaros said. “We are the ones.”

As deeply indebted European nations undergo waves of harsh government cuts in exchange for European Union-backed bailouts, observers warn that the fabric of society in some countries is being stretched to its breaking point. As countries trim spending, the elderly and disabled are enduring deep reductions in aid and pensions. Workers are losing their jobs or facing sharp salary cuts. Taxes are increased in the middle of steep recessions.

Other hot spots in Europe

The crisis has fanned the fires of independence in Catalonia and Dutch-speaking Belgium, threatening to break up the Spanish and Belgian states. But nowhere is the stress of the crisis more profound than here in Greece, where the deepest of cuts have left a grim tableau. One in every four Greeks is without work. Youth unemployment is above 50 percent. The suicide rate is climbing. Medical treatments for cancer and other illnesses have become harder to get. Growing intravenous drug use is causing a spike in the rate of HIV infection, according to a study published in the Lancet medical journal.

The collapsed economy is fertile ground for the Golden Dawn. Born in the 1980s and populated by Greek nationalists, including some who fought with the Serbs in the Balkans and had ties to Greece’s former military dictatorship, the party won its first-ever seats in Parliament in May with 7 percent of the vote. A recent poll showed that 22 percent of Greeks view the party favorably.

To be sure, nationalist and ­anti-immigrant parties are rising across Europe. But observers put the Golden Dawn in a league of its own. In 1987, the magazine of the party — headed by Nikolaos Michaloliakos, a former commando in the Greek special forces — published an issue hailing Hitler as “the great man of the 20th century.” On a recent visit to the help bureau, a poster heralding the Third Reich’s 1936 Berlin Games hung on a wall.

In a nation where memories of World War II-era atrocities remain fresh, polls have shown that most Greeks who support the Golden Dawn are doing so based solely on its anti-immigrant stance and that they largely dismiss the group’s more hard-core attributes. But its extracurricular activities are becoming more violent.

“They speak of ‘cleaning-up’ operations,” said Vassiliki Georgiadou, an academic who has studied the movement. “They will try, violently if needed, to ‘clean up’ whole neighborhoods, towns, the country.”

Greek Justice Minister Antonis Roupakiotis said he is concerned about the party’s alleged ties to the police and military. Accusations are rife that police may be working with the Golden Dawn on a new nationwide stop-and-search campaign targeting illegal immigrants. Activists also allege that segments of the police may be colluding with the party in anti-immigrant attacks, which the government estimates number at least two or three a week.

There have been limited attempts to investigate the party, including lifting parliamentary immunity for two Golden Dawn legislators who were recently videotaped harassing an immigrant market. But critics say the government has been reluctant to more broadly confront the party’s alleged abuses. Rather than banning the party, as some here suggest, Roupakiotis said the best solution is to improve social conditions in Greece to undermine the Golden Dawn’s strength.

‘Taking advantage’

“Greece fought the fascists in World War II, thousands of Jews ended up in crematoriums and now we are facing this threat again,” Roupakiotis said. He later added: “This is being caused by the tough conditions Greece is being forced to endure. Extremists are taking advantage of the situation.”

Yet Roupakiotis and others also blame the heavy flow of migrants from the Middle East and Asia who use Greece as a back door to enter the European Union, most often via Turkey. The situation is being made worse by European policies that allow E.U. countries to deport undocumented immigrants to their entry point in the union, often meaning Greece. As a result, the population in Greek jails is 40 percent non-Greek.

Since the Golden Dawn’s rise to office this year, immigrant communities across Greece are reporting what they describe as a reign of terror. In the America Square neighborhood of Athens, for instance, immigrants have begun organizing night watches after shopkeepers had their storefronts vandalized and immigrant men were assaulted. Earlier this month, residents say, a group of Greek men dressed in black stripped and humiliated an Ethiopian woman.

Some alleged attacks involve nothing more than insults. Others are more serious.

On Sept. 22, Ali Riasat Ghulam, a 47-year-old Pakistani man who has lived in Greece for 22 years, was at a gas station near his home in northern Athens. Two Greek men clad in black drove up in a car. The men, he said, asked him where he was from. After Ghulam replied “Pakistan,” the men attacked him with a knife, leaving him with three stab wounds that are still healing, including a 12-inch circular gash on his chest.

“We are terrified,” said Ghulam, who shares a rundown apartment on the edge of Athens with five other Pakistani immigrants. “We do not go out alone anymore, not even to the grocery store. We know the Golden Dawn is out there.”

Elinda Labropoulou contributed to this report.