May 1, traditionally recognized as May Day, was marked with violent protests in cities across the globe. Boosted in large part by the Occupy Wall Street movement that seized worldwide attention last fall, some considered the date to be a restart of the group’s operation, which lost momentum over the cold winter months.

Thousands swarmed the streets across Spain, Portugal, Italy, France and Greece, showing their anger over austerity measures by vandalizing buildings, looting shops, and blocking roadways. Likewise, demonstrations in Oakland, California, and Seattle, Washington, turned violent as protesters smashed windows, and were chased through the streets by police in riot gear, according to Reuters.

Disruptions took many different forms. Five anarchists in Cleveland attempted to blow up a heavily trafficked bridge “in order to send a message to corporations and the United States government,” according to USA Today.

In New York City, several banks received threatening letters containing a “white powder,” an apparent play on the anthrax scare of a decade ago. A spokesman for Occupy Wall Street claimed in an Associated Press article that the “prank” had nothing to do with its protest movement. Others in the New York area vandalized banks and blocked people from accessing money through ATMs.

“In Santiago, Chile, police blasted demonstrators with water cannons, and in Bogota, Colombia, activists ran through a flooded street to escape tear gas fired by authorities,” another Associated Press article stated. “Demonstrators in the Philippines and Bolivia burned effigies of their countries’ leaders.”

May Day, which is an ancient spring festival, was more recently co-opted as International Worker’s Day by the global labor movement. The day is typically observed with demonstrations by workers around the world.

One participant shared with Reuters, “Right now I’m really excited about laying the groundwork for a long-term struggle. That’s what I see May Day as being. I’m really looking at May 1 as a catalyst for the rest of the month.”

Analysts warn this may be just the beginning of a summer of unrest, similar to what occurred in Britain in August 2011.

“Many newspaper articles have said that one cost of enforced austerity will be social unrest,” The Wall Street Journal quoted Bill O’Donnell, RBS Securities lead treasury strategist, as saying. “Think back to the Villiers-le-Bel riots in France in 2007, the Clichy-sous-Bois unrest in France in 2005 and the Brussels riots of 2006. All this unrest was a possible precursor to the so-called Arab Spring and the participants were typically unemployed youth, many of whom were ‘disenfranchised’ immigrants.”

He likened the 50 percent unemployment rate for those under 25 years old, as seen in Spain and Greece, to “a pile of tinder waiting for a match.”