While blockers and police officers clashed downtown on May Day, protesters in midtown marched down the streets armed with guitars, melodicas, and cellos.These participants were part of the Occupy Guitarmy, a group of protesters who performed music while marching to the free May 1st concert at Union Square — where they later joined guitarist Tom Morello on stage.

The Guitarmy was co-organized by Alphonzo Terrell, 29, and “Goldi,”  44, as a part of the Occupy Wall Street Music Working Group.

“We’re bringing an army of guitars,” said Goldi, “ to outreach the message of our movement, which is more economic equality for more people and a more just world that we don’t have thanks to American crazy policy. But now we’re doing it through music and hopefully we’ll reduce the amount of police battles we have today because we’re playing music.”

Essentially, the idea behind the protest was that a song cannot be arrested. The marchers played and sang “This Land is Your Land” by Woody Guthrie, “Which Side Are You On?” by Florence Reece, the spiritual “We Shall Not Be Moved,” “World Wide Rebel Songs” by The Nightwatchmen, “El Pueblo Unido”  by Chilean folk group Quilapayun, and “One Guitar” by Willie Nile.

The relationship between music and protests has existed for many years, from the early songs of Woody Guthrie to Civil Rights folk songs and the anti-Vietnam War movement with artists such as Pete Seeger and The Fugs. More recently, Arcade Fire, Le Tigre, and Conor Oberst incarnated these new form of protests.

“Music is a really important thing to unify and rally people,” said Flora Newberry, a 46-year-old music teacher at Westminster Conservatory of Music in Princeton, New Jersey. “It’s something that everybody relates to — it gives the movement energy.”

The march from Bryant Park to Union Square started at 2 p.m. Rehearsals however began around noon. While hundreds of people occupied the south end of Bryant Park with posters and a loud and massive drum circle, around 50 people with acoustic guitars and other instruments congregated near the Gertrude Stein statue at the north end of the park. They simultaneously practiced renditions of the selected songs in different groups. More people eventually showed up, including Yes Men activist and former Parsons professor Andy Bichlbaum who was seen playing a mandolin.

The area gradually grew more crowded and chaotic. Some participants created homemade shakers using pastel-colored plastic easter eggs filled with seeds and taped together. Protesters passed around printed “cheat sheets” with the chords and lyrics to some of the songs.

Tom Morello, guitarist for Rage Against The Machine and The Nightwatchmen, showed up around 1 p.m.  and led a mic check announcing the commencement of the march.

At 2 p.m., hundreds of Guitarmy members coalesced with the Bryant Park occupiers and walked on Fifth avenue, starting with the song “Which Side Are You On.”

While approaching 32nd Street, they were met with a surprisingly lenient response from the NYPD, unlike the violent clashes happening at the same time between protesters and police officers in other parts of the city.

The bulk of the march ended at Union Square around 3:30 p.m., with thousands of people crowding around the stage set up at the south end of the park.

A free May Day concert began at 4 p.m., opening with Tom Morello. About 30 Guitarmy performers joined him on stage to perform “World Wide Rebel Songs, continued by a rendition “This Land is Your Land.”

His performance was followed by Latin jazz percussionist Bobby Sanabria. He performed in an ensemble comprised of Local 802 union members, which represents musicians. After their performance, he asked attendees to email “The Grammys” in protest of their cut of 31 categories, including Best Native American album.

Brooklyn hip-hop trio Das Racist then took the stage, performing their songs “Michael Jackson” and “Rainbow in the Dark.” They went over the allotted time and eventually had their microphones and audio shut off. Undeterred, they continued without mics, with audience members rapping along.

Baltimore-based electronic artist Dan Deacon performed afterwards, calling people to start a “physical body mic check.” Famous for audience participation in his performances, he asked the crowd to go on their knees, encircle and mimic a man named Greg in the middle.

“We’re going to do this with a hive mentality,” Deacon said during the performance. “Greg is going to be the Queen Bee. We, the faithful drones.”

The New York City Labor Chorus, comprised of older women and men donning matching shirts, also performed a jazzed up, gospel version of Ralph Chaplin’s pro-union tune “Solidarity Forever.”

Afro-Peruvian-American rapper Immortal Technique was the final singer. He performed his songs “Leaving the Past” and “Toast to the Dead.” The often-outspoken artist told the NYPD officers next to the stage, “You’re part of the 99 percent too.”

The concert ended at 5:30 p.m., and the march continued down to Wall Street.